The United States Defence Secretary, Mr Donald Rumsfeld, sent a Cold War chill across the Atlantic yesterday, accusing Russia of selling missile technology to Washington's enemies.
"Let's be very honest about what Russia is doing," he said. "Russia is an active proliferator. They are part of the problem."
In comments that drew an angry response from Moscow, Mr Rumsfeld said: "They are selling, and assisting, countries like Iran, North Korea and India and other countries with these technologies, which are threatening other people, including the United States, Western Europe and countries in the Middle East."
In his hardest-hitting policy statement on Russia since becoming Defence Secretary last month, Mr Rumsfeld said Moscow's action made it all the more necessary for the US to deploy a National Missile Defence(NMD) system.
"Why they [the Russians] would be actively proliferating, and then complaining why the United States wants to defend itself against the fruit of these proliferation activities, it seems to me is misplaced."
Moscow, once it had sorted out Mr Rumfeld's grammar, gave an icy response: "This is rubbish, there is nothing of the sort going on," said the Russian Defence Minister, Mr Igor Sergeyev. "I find it difficult to react to these ravings."
At issue is the plan by the United States to deploy a system capable of shooting down ballistic nuclear missiles.
Russia says the system would break the 1972 Anti Ballistic Missile Treaty.
But Mr Rumsfeld, interviewed by a US TV network, said Russia was "not really serious" about opposing NMD because it is a "point" system, designed to knock down individual missiles, not the mass attack Russia can mount.
Russia's Deputy Chief of Staff, Gen Valery Manilov, said Mr Rumfeld's comments were aimed at US public opinion, hoping to gain support for NMD.
He denied the allegations: "Russia has not, does not and will not renege on its non-proliferation commitments," he said.
Mr Rumfeld's statement comes a few days after the US National Security Adviser, Ms Condolezza Rice, branded Russia "a threat" to the West. Earlier this month, a CIA report said Russia's president, Mr Vladimir Putin, "wants to restore some aspects of the Soviet past."
None of this is likely to make for an easy first visit to Moscow later this month by the US Secretary of State, Gen Colin Powell. Russia says it may counter NMD by deploying extra nuclear missiles.
One compromise Gen Powell is likely to explore is that the US could expand any such "point" system to cover both Russia and Western Europe.