George Osborne, Ed Balls and Vince Cable have put their political differences on ice to warn of the economic risks of breaking away from the EU. The Conservative chancellor, former Labour shadow chancellor and ex-Liberal Democrat business secretary stood side-by-side at Stansted Airport to issue their pro-EU plea on 16 May.

"We fought issue at the last general election with different economic arguments and we have clashed repeatedly in the House of Commons over the years, but there is one thing that we all agree on and that is that it would be a huge mistake for Britain to leave the EU and to leave the single market," Osborne argued.

The top Tory also accused Brexit campaigners of believing in a "global stich-up" to keep the UK inside the 28-nation-bloc.

"The next thing we know, the leave camp will be accusing us of faking the moon landings, kidnapping Shergar and covering up the existence of the Loch Ness monster," Osborne joked.

"The response to the sober, economic warnings from around the world by those who want to leave the EU has not been credible or serious.

"And there's a reason that the three of us are standing here today, putting aside our very obvious differences. It's not a conspiracy, it's called a consensus."

The comments come ahead of Boris Johnson's visit to the East Midlands city of Nottingham, as part of Vote Leave's battle bus tour of the UK. The former London mayor has said he does not want the UK to be part of the European Economic Area (EEA) after a 'leave' vote. Osborne claimed such a move would be a "disaster" for the British economy.

But more than 300 UK business leaders have signed a pro-Brexit letter, published in The Daily Telegraph. The signatories, including Superdrug co-founder Peter Goldstein, claimed the UK's competitiveness was being undermined by the EU.

"Year-on-year the EU buys less from Britain because its economies are stagnant and millions of people are unemployed," the letter said.

"It is business – not government – which generates wealth for the Treasury and jobs for our communities. Outside the EU, British business will be free to grow faster, expand into new markets and create more jobs. It's time to vote leave and take back control."

George Osborne and Ed Balls
George Osborne and Ed Balls campaigned alongside Vince Cable at Stansted AirportGetty