A DEMOCRATIC European Union is “urgently and vitally needed,” John McDonnell told leftwingers pushing to stay part of the neoliberal trading bloc on Saturday.

The shadow chancellor joined a host of speakers at the Vote In — Another Europe is Possible conference, including former Greek finance minister Yanis Varoufakis, Green Party MP Caroline Lucas and journalist Owen Jones.

He told the London rally that the movement to reform the EU into a democratic force has been growing across the continent.

“We have the opportunity to regroup the referendum debate away from Tory Brexit and into a debate on a democratic Europe,” he said.

“A Europe that is not just possible but is urgently and vitally needed — where we can say yes, we are proud of being British, but we are also proud of the European future we have created.”

Mr McDonnell blamed the Tories for dragging the debate “into the intellectual gutter” and “disfiguring political discourse.”

He added that transnational problems needed transnational solutions, including the offshore tax haven scandal and the refugee crisis.

Mr Varoufakis, who during his stint in the Greek government was critical of the EU and the swingeing cuts it demanded in return for bailout cash, echoed Mr McDonnell’s words warning that Brexit would ”only benefit a national oligarchy.”

The packed hall at the Institute of Education also featured speakers from trade unions, Young Labour and a host of grassroots organisations.

But left leave campaign Lexit chairman Rob Griffiths told the Star: “The reality is that another Europe is impossible.

“This is because the EU is committed to free-market, big-business capitalism, things written into the basic treaties of the EU.

“Workers will have to fight against the EU in order to create a new socially just order in their own countries.”

The campaign’s next public meeting will take place on June 3 in Sheffield, with Green Party leader Natalie Bennett and Labour MP Clive Lewis on the panel.