The battle for Donbas: ‘the real test of this war’

Next phase of war likely to determine course of Russia’s invasion – and Ukraine’s fate

It began with heavy shelling overnight that levelled three-storey residential blocks, hit the town’s nursing home and left four-foot deep craters in the road. Then the heavy armour rolled in.

Dozens of Russian tanks, self-propelled guns and armoured personnel carriers advanced on Kreminna from three directions, as residents attempted to flee. After attempting to hold the town over the course of last weekend, Ukrainian troops retreated last Monday.

The small town of less than 20,000 people in eastern Ukraine is no standout victory for the Russian army, which two months ago launched an invasion aimed at capturing Kyiv and toppling the country's pro-western government in a matter of days.

But the successful capture of the town, which lies on a crucial junction between a major north-south highway, represents not just the first accomplishment of Russia’s new strategy to focus its forces on Ukraine’s war-torn east, but also the execution of a more traditional form of grinding warfare after weeks of failed strategies and tactical errors.

'The real test of this war, and indeed of Ukraine's true ability to withstand the Russian onslaught, is coming now'

"Kreminna is under the control of the orcs. They have entered the city," Serhiy Haidai, governor of the Luhansk region where Kreminna is located, said on Tuesday, using the Ukrainian pejorative to describe Russian forces. "For each of our platoons, they sent 40 armoured units."

In what is likely to be a brutal and bloody onslaught on Ukraine's east, the Kremlin's aim is to secure the whole of Luhansk and neighbouring Donetsk. Together they are known as Donbas, a vast region of which roughly a third is already controlled by pro-Kremlin separatists since a Russian-fuelled insurgency that followed the 2014 annexation of Crimea.

Standing in Russia’s way are the troops of the Joint Forces Operation (JFO), some of Ukraine’s best trained and most battle-hardened soldiers, who have been dug into defensive positions for much of the past eight years. About 40,000 troops were stationed there before the conflict exploded in February, about a quarter of the Ukrainian army, and they will have since been reinforced.

"We will see Russia mounting more of a vigorous campaign. I have seen some people saying it could be like the second World War," says a senior Nato official. "Look, it could also be more like the first world war, given the defences that have been built – the trenches, the bunkers since 2014."

Failed strategy

Russia’s decision to shift the bulk of its 190,000 troops involved in the invasion of Ukraine to fighting in the east of the country comes after its initial strategy of a lightning assault on the capital in conjunction with unco-ordinated attacks into the south and north-east of the country failed to make major gains.

Ukrainian troops, better armed, better trained and more determined to resist than Moscow had expected, held back seven weeks of attacks on Kyiv, and prevented Russian assaults from capturing key cities such as Kharkiv in the north-east and Mykolayiv on the southern coast, inflicting larger than anticipated losses on the invading force.

Russia’s military has officially brushed off those failures and claimed the new approach was part of the plan. On Friday, a senior Russian commander said troops were set on “establishing total control of Donbas and southern Ukraine”.

That would “allow us to set up a land corridor to Crimea and affect vital parts of the Ukrainian economy,” said Rustam Minnekayev, acting commander of Russia’s central military district.

How the battle for Donbas unfolds is likely to determine the course of the entire invasion, and the fate of Ukraine’s postwar existence.

If Russia is able to make major gains in the north and south of Donbas, it could cut off the JFO from western military reinforcements and potentially encircle and trap a significant chunk of the Ukrainian army – an outcome that would undermine efforts by Kyiv to defend a potential renewed Russian assault on western Ukraine.

A Russian-controlled Donbas, alongside Moscow's capture of Ukraine's eastern coastline and a land bridge to Crimea, would give Russian president Vladimir Putin tangible victories from his invasion, as well as huge leverage in any peace negotiations with Volodymyr Zelenskiy, his Ukrainian counterpart.

Ukraine’s military successes in the first two months of the war came from using guerrilla style tactics and the innovative use of short range anti-tank and anti-aircraft weapons supplied by the West. But that approach is less likely to work in the more set-piece battles many expect in Donbas.

“The real test of this war, and indeed of Ukraine’s true ability to withstand the Russian onslaught, is coming now, when Moscow finally gets its organisation sorted and lines up its forces in the east the way they were trained to fight,” says a senior western defence official.

“A solid line of armoured infantry at the sharp end, and then behind them, safe and protected, all the artillery, rockets and whatever else they fancy lobbing with utter impunity at the Ukrainian defences,” the official adds. “That’s a very, very different prospect to what the Ukrainians have dealt with so far.”

Relentless attacks

In preparation for the onslaught, Russia began a process of intense shelling and missile strikes on April 18th in south eastern Ukraine and along the Black Sea coast. The US Pentagon has described this as a shaping operation designed to disrupt the flow of western weapons and other logistical support to the Ukrainian army – especially of fuel.

Ukrainian forces on the Donbas front line, which stretches some 500km, north to south, describe relentless attacks by Russian howitzers, mortars and multiple rocket launchers, as well as by helicopters and low-flying planes.

At a checkpoint north of Avdiyivka, south of Kramatorsk, a military police guard said shelling of the city has become intense. “It gets very loud,” he said. “They are throwing phosphorus bombs all over the place. The sky lights up.”

At the same time, Ukrainian troops who are braced for the assault said they were confident of repelling any Russian advance, pointing to their much improved weaponry and their eight long years of being stationed in what is now set to become the front line.

In preparation for a new offensive, fresh defensive fortifications are being built all across Donbas. During a recent visit to the region, a Financial Times correspondent witnessed how the Ukrainian military has been shipping in fresh arms, supplies and fuel.

Maj Gen Eduard Moskalyov, a commander of Ukraine's forces in Donbas, said Russia had deployed its "most combat ready units". "We very well understand how strategically important Donetsk and Luhansk regions are for the plans of the enemy," Moskalyov said.

But he added that the Ukrainian forces were “already for eight years defending” the region against Russian “enemy attacks on our independence and freedom”.

Russia's main targets are Slovyansk and Kramatorsk, adjacent cities deep inside Ukrainian lines that hold the key to control of Donbas, western defence and intelligence officials say. Moscow aims to reach them through three assault axes: south from Izyum, north from Donetsk, and west from Severodonetsk – the route that took troops into Kreminna.

“We believe they want to close in on Donbas from the north and from the south,” says a senior US defence official. “We’re already seeing the efforts to do that from the north so that they can fix Ukrainian forces there and eventually finish them or force them to surrender.”

Ukrainian forces, potentially outnumbered three to one by the Russians according to western defence officials, have meanwhile run low on ammunition and other weapons.

The biggest question remains whether Russia’s armed forces will successfully co-ordinate their assault in a combined arms operation that synchronises ground, air and artillery attacks. In the opening weeks of the invasion, Russia attacked from multiple directions with the commanders of its four military districts acting autonomously. That lack of co-ordination stymied the effectiveness of the attacks.

The appointment in mid-April of Gen Alexander Dvornikov as the sole invasion commander in Ukraine represents a belated attempt by Moscow to remedy its mistakes.

Air support

The Russians’ “command and control has become more effective” says a western official. “[But] what they’re not yet doing is operating ... as a truly manoeuvrable force,” he adds, citing the continued use of exposed roads for transport, leaving vehicles vulnerable to ambush.

The Donbas region borders Russia, which should aid better supply and communication lines, avoiding the calamities seen near Kyiv, where a 60km-long convoy of tanks, troop carriers and military equipment was left stranded for days after it ran out of fuel, food and adequate leadership.

The proximity of Russian airfields, such as Millerovo, where Su-30 and MiG-29 fighter jets are based, and Morozovsk, home of the 559th Bomber Regiment, will also give the troops on the ground far better air support than they had in other areas of Ukraine.

Even so, Donbas is still a complex operation, covering some 52,000 sq km, almost the same size as Slovakia. The heavy rain of a wet winter has also turned its flat terrain into a muddy bog, which western defence officials and analysts say will limit the ability of Russian armoured forces to manoeuvre.

“The Russian army has two main options,” says Samuel Cranny-Evans, a military analyst at the Royal United Services Institute think-tank in London. “They might try and take the whole area in one concerted push – but that’s very ambitious.

“Alternatively, they could take bite-size chunks out of the Ukrainian front line by encircling pockets of troops in strategic areas, cutting them off with electronic warfare and using artillery to stop reinforcements, and then squeezing them in small cauldrons,” Cranny-Evans adds.

That would follow the pattern of Russia’s onslaught in the besieged city of Mariupol, where troops divided it into different areas and squeezed each one tightly so that, as Putin put it on Thursday, “a fly can’t get in”.

Ominously, a similar process happened in Donbas in 2014, when Russian-backed separatists encircled Ukrainian fighters in the city of Ilovaisk – and then, after they surrendered, reneged on an agreement that would have let them withdraw unharmed along humanitarian corridors. Survivors later described it as a “massacre”.

‘Intense fighting’

The prospect is of a gruelling and drawn-out battle by troops on both sides that are already exhausted. Estimates vary widely, but western defence officials believe Russia has about 76 battalion tactical groups, the primary units of the army comprising around 800 troops plus armour and artillery, already deployed in Donbas, with another 22 being refitted outside Ukraine. The fall of Mariupol is also expected to free up another 5,000 to 10,000 Russian troops.

Moscow has added new artillery, helicopters, and command and control assets to the east in recent weeks, mainly shifted from the failed assault on Kyiv, the senior Nato official says, adding that the result was likely to be “fighting that is very intense ... in terms of the violence”.

If these additional assets are all fed into the battlefield, Russian forces may total as many as 80,000 troops – although their morale and desire to fight is widely reported to be low.

"[Russia] has a lot of mass ... they'll hammer the Ukrainians with artillery, missiles, rockets, and bombs," says David Petraeus, retired US four-star general and former CIA director. "The Ukrainians are undoubtedly going to have to give some ground, but I don't think the Russians are going to achieve a real breakthrough.

“I just haven’t seen any evidence that the Russians have gotten their act together,” says Petraeus. “The whole is not greater than the sum of the parts because they aren’t employing the parts in a complementary fashion.”

In preparation for the onslaught, Zelenskiy has repeatedly called for more help – with long-range artillery and armoured drones that can probe deep behind the front line to destroy Russia’s heavy artillery top of his wish list.

Among the western allies scrambling to supply Ukraine with heavier weaponry, the Czech Republic has provided T-72 tanks and the UK is sending Stormer armoured missile launchers.

A new package of US assistance announced last Thursday includes 72 155mm Howitzers guns and 144,000 artillery rounds, which in addition to the 18 Howitzers previously announced provides enough artillery to equip five Ukrainian battalions, according to a senior US defence official.

But, say defence officials, the Ukrainians still need more as the conflict drags on.

Declaring ‘victory’

Zelenskiy has constantly repeated that the end of the conflict can involve no loss of Ukrainian territory. By contrast, Russia’s goals have evolved during the fighting, as has Moscow’s definition of what winning means.

Putin may want to brandish a victory of some sort on May 9th, when an annual military parade in Red Square commemorates the defeat of Nazi Germany in 1945. "I am not a big believer in fetishising dates," says Michael Kofman, lead Russia analyst at the CNA think-tank. "But it is true that the Russian military needs to deliver some kind of success."

In a best-case scenario for Ukraine, its troops could hold back or even repel the Russians. In a worst-case scenario, the opposite is true, with Russia even trying to renew its attack on Kyiv or on the key port of Odesa.

“Trashing Ukraine and making the West look weak, with the ultimate aim of strengthening the regime’s hold on power, is what drives Kremlin policy at the moment; with Putin as the winner and the only person who can save Russia,” says one European intelligence officer.

Certainly, Moscow shows no sign of paring back its self-described “special operation” that, with the blessing of Patriarch Kirill, leader of the Russian Orthodox Church, has taken on aspects of a crusading holy war to restore Russian glory and statehood.

“Even though Russia’s operational focus has shifted to the east, we still see that Russia’s ultimate objective remains the same, which is to use military force to compel Ukraine to abandon its Euro-Atlantic orientation, and by extension reassert [Moscow’s] regional dominance,” says the senior Nato official.

As Russian soldiers hung the country’s tricolour flag on the door of Kreminna’s administrative headquarters last Tuesday, locals took photographs of fighter jets roaring overhead and shared to social media footage of the damage to their homes from artillery strikes.

Haidai, the regional governor, urged them all to flee. “Save your lives so as not to become a cheap labour force or be mobilised into the occupation troops. Those who do not agree, the Russians kill on the spot,” he said in a plea posted to his personal Telegram account. “Evacuate to safe regions of Ukraine ... Buses are waiting.” – Copyright The Financial Times Limited 2022