Ahead of the gatherings, diplomats and officials believe that Germany is unlikely to join any European peacekeeping efforts that could follow a ceasefire in Ukraine.

Poland has ruled itself out of such a mission because Warsaw's troops are committed to protecting Nato's eastern flank.

Both Hungary and Slovakia are also highly unlikely to join given their governments' close ties with the Kremlin.

Many European nations, such as Spain, Italy and Norway, have remained on the fence, leaving some capitals despondent over the possibility of a peacekeeping operation.

"The whole discussion is moot without both Germany and Poland's participation," a diplomatic source said.

Many of Europe's militaries have been significantly depleted since the end of the Cold War.

Lord Dannatt, who was the Army's chief of the general staff between 2006 and 2009, said that Britain does not have the forces or equipment "to put a large force on to the ground for an extended period of time".

Sir Ben Wallace, the former defence secretary, has previously told The Telegraph that the British military would be unable to stand by its previous commitments as well as send troops to Ukraine.