Relations between Russia and Ukraine have always been difficult. Since Ukraine's Orange revolution in late 2004 they have been dismal. Conflicts have involved gas, agricultural trade, the Russian naval base in the Crimea, the war in Georgia and Ukraine's interest in Nato. Even so, politicians from the two countries rarely meet.

Last year Vladimir Putin, then Russia's president, escalated the conflict by publicly questioning Ukraine's sovereignty and territorial integrity. He has repeated his claims as prime minister. President Dmitri Medvedev's strident open letter to President Viktor Yushchenko amounted to a further escalation, with its declaration that Russia would not send a new ambassador to Kiev. Mr Medvedev offered no constructive proposals but listed old Russian grudges, claiming that all faults lie with Ukraine.

The language was reminiscent of Leonid Brezhnev in its detachment from reality. Mr Medvedev claimed that no Russian threat against Ukraine exists, as if he were unaware of his prime minister's statements. He went on in Soviet vein: “Russia endeavours to be a predictable, strong and accommodating partner” to its neighbours. Well, hardly, as Mr Yushchenko noted in his response.