Russia and Ukraine will hold their first peace talks in almost three weeks on Tuesday morning in Istanbul amid a looming humanitarian collapse in besieged Ukrainian cities.
Adding tension to the latest talks are reports that attendees of previous rounds, including Ukrainian officials and Russian oligarch Roman Abramovich, suffered severe symptoms of poisoning.
On Monday the mayor of Mariupol, the devastated port city, said at least 5,000 residents had been killed and 160,000 remained trapped without power and with dwindling food.
Four weeks into the conflict, Ukrainian president Volodymyr Zelenskiy said he would drop any Nato membership ambitions in favour of a "neutrality, non-nuclear status". But Kyiv officials, hopeful Russia has lost military momentum and is retreating east, say they will make no concessions on ceding territory.
"I don't think there will be any breakthrough on the main issues," said Ukrainian interior ministry adviser Vadym Denysenko.
Separately, US president Joe Biden said on Monday his weekend comments that Russian president Vladimir Putin “cannot remain in power” reflected his own “moral outrage” at his behaviour in Ukraine and not did not represent a major policy change by the White House.
Speaking at a press conference in Washington, Mr Biden said: “No one believes we’re going to take down Putin.” The president said he was “not walking anything back” by clarifying the ad lib remarks he made regarding Mr Putin at the end of a speech in Poland on Saturday.
“I wasn’t then nor am I now articulating a policy change. I was expressing moral outrage that I felt and I make no apologies,” he said.
As officials from Russia and Ukraine arrived in Istanbul on Monday evening, the Bellingcat investigative collective revealed details of the suspected poisoning after a March 3rd meeting in Kyiv.
The session concluded at about 10pm and at least two members of Ukraine’s negotiating team, including Ukrainian MP Rustem Umerov, experienced skin inflammation and piercing eye pain during the night and the following day.
Experts consulted were unable to collect timely samples required for full analysis but, according to Bellingcat, “concluded that the symptoms are most likely the result of intentional poisoning with an undefined chemical weapon”.*
A spokesman for Mr Abramovich confirmed the incident, first reported by the Wall Street Journal, and said his symptoms subsided after a week.
Asked about the suspected poisoning, Ukrainian negotiator Mykhailo Podolyak said “there is a lot of speculation, various conspiracy theories”. Reuters news agency quoted an unnamed US official, citing intelligence, blaming an “environmental” reason for the sickening, and not poisoning.
Ahead of Tuesday’s talks, officials in Irpin near Kyiv, a front line in the conflict, announced that Ukrainian forces had taken back the town from Russian troops.
"Irpin has been liberated," said mayor Oleksandr Markushyn in a video post on Telegram, a claim yet to be independently confirmed. The mayor urged residents not to return yet as they were expecting further attacks as they "carry out a mopping-up operation".
A US official said Ukrainian troops had taken back a second town – Trostyanets, south of Sumy – and were "continuing to take back ground". Last week, after a month of fighting and no major cities taken, Russia's defence ministry insisted its main objective had always been to "liberate" eastern regions controlled by Russian-backed separatists.
Kyiv mayor Vitali Klitschko said on Monday more than 100 people had died in the capital, with more than 20 unidentified corpses including four children, and "many corpses and pieces of human corpses" on the streets.
Amid fresh demands for parties in the conflict to agree to humanitarian corridors, UN secretary general António Gutteres said he was “talking to parties at the highest level to explore different forms of mediation leading to a political solution”.
Russia's last independent news outlet, Novaya Gazeta, is to suspend publication after its Nobel Peace Prize laureate, editor Dmitry Muratov, participated in a video interview on Sunday with the Ukrainian president.
On Monday, G7 nations dismissed a Russian demand to pay for energy imports in roubles as "a unilateral and clear breach of existing contracts".
*Article amended on March 31st