Any western leader negotiating over the fate of smaller countries in central or eastern Europe does so in the shadow of two bitter historical experiences: the Munich agreement of 1938 and the Yalta agreement of 1945. At Munich, the British and the French agreed to Adolf Hitler’s demands for the dismemberment of Czechoslovakia – without the participation of the Czech government, which was not represented at the talks. At Yalta, the British and the Americans made a deal with Josef Stalin that, de facto, accepted Soviet domination over postwar Poland and other countries under Russian occupation – again, without the participation of those concerned.

These parallels – in particular, Munich – are weighing heavily on western leaders as they attempt to chart a way forward over Ukraine. “We will not accept a path forward where the legitimate government of Ukraine is not at the table,” said John Kerry, the US secretary of state, at the conclusion of weekend talks in Paris with Sergei Lavrov, the Russian foreign minister.

Wolfgang Sch?uble, the German finance minister, yesterday compared President Vladimir Putin’s claim that he is acting in defence of the rights of ethnic Russians in Ukraine to Hitler’s claim that he was acting to defend the rights of ethnic Germans in Czechoslovakia. The parallel has also been made by Mr Kerry’s predecessor, Hillary Clinton.