War criminal Tony Blair made an unwelcome return to the political stage yesterday to express his “100 per cent support” for Labour leader Ed Miliband’s election campaign.

The arch-rightwinger praised Mr Miliband’s desire to deny the British people a say on EU membership, claiming an exit would cause economic “chaos.”

But droves of people inside and outside the party thought the ex-PM should have kept his mouth closed, branding the “toxic” intervention hypocritical.

Labour leftwinger John McDonnell told the Star: “Tony Blair would make the best contributions to our campaign by remaining silent.”

In a high-profile visit to his former Sedgefield constituency, Mr Blair said: “I believe passionately that leaving Europe would leave Britain diminished in the world, do significant damage to our economy.

“Think of the chaos produced by the possibility, never mind the reality, of Britain quitting Europe.“And for what? To satisfy the insistent Europhobia of a group who will never be satisfied.”

Cross-party campaign People’s Pledge co-founder Stuart Coster hit back: “In 2004 Tony Blair said he wanted to confront Eurosceptics and make the case for Europe, agreeing people should have the final say.

“Yet today, shamefully, it seems he’s running scared of that vote.

“Under Blair, Labour was the party of referendums. Dozens were held on subjects from devolution to regional assemblies and elected mayors.

“It’s lamentable that Blair is now encouraging Ed Miliband to lead Labour away from that proud democratic tradition and is praising his refusal to give people a say on the extent to which Britain is governed by EU institutions.

“Anyone would be forgiven for thinking that Tony Blair’s reversal to near-hysterical opposition to an EU referendum says more about still having his eye on the job of EU president than about what’s right democratically and best for Britain’s future.”

Others also took exception to Mr Blair’s involvement in Labour’s campaign, given his invasion of Iraq.

Comedian Frankie Boyle took to Twitter to vent his frustration: “Tony Blair, who killed hundreds of thousands ‘promoting democracy’ joins the fray to protest about people voting on something.”