Part of the statement read: “The conflict is the product of 30 years of failed policies, including the expansion of Nato and US hegemony at the expense of other countries as well as major wars of aggression by the USA, Britain and other Nato powers which have undermined international law and the United Nations. 

“The British Government has played a provocative role in the present crisis, talking up war, decrying diplomacy as appeasement and escalating arms supplies and military deployments to eastern Europe.

“If there is to be a return to diplomacy, as there should be, the British Government should pledge to oppose any further eastward expansion of Nato and should encourage a return to the Minsk-2 agreement, already signed by both sides, by all parties as a basis for ending the crisis in relations between Ukraine and Russia.”

‘Give succour to authoritarian leaders’

Earlier this month Sir Keir criticised Stop The War in an article published in The Guardian. 

Sir Keir wrote: “At best they are naive, at worst they actively give succour to authoritarian leaders who directly threaten democracies. 

“There is nothing progressive in showing solidarity with the aggressor when our allies need our solidarity and – crucially – our practical assistance now more than ever.”

In the past supporters of Stop The War have dismissed criticism aimed at them and argued their campaigning is focused on securing peace.