Boris Johnson has thrown his weight behind a new group putting pressure on Theresa May to deliver a ‘hard Brexit’

Boris Johnson has thrown his weight behind a new group putting pressure on Theresa May to deliver a ‘hard Brexit’.

In the latest sign of tensions between the Brexiteer Ministers and No 10, the Foreign Secretary will help the group, Change Britain, to demand measures such as pulling the UK out of the single market.

Change Britain, which launches today, is backed by an array of high-profile Brexiteers including former Tory leadership contender Michael Gove, Margaret Thatcher’s Chancellor Nigel Lawson and David Cameron’s former adviser Steve Hilton.

The aim is to ensure that Mrs May does not try to negotiate a form of ‘Brexit-lite’ involving compromises over immigration controls in exchange for greater access to the single market

In a video address to mark the campaign’s launch, Mr Johnson said: ‘Brexit means Brexit and that means delivering on their instructions and restoring UK control over our laws, borders, money and trade.’

Mr Johnson also calls for ‘leavers and remainers’ to ‘seize the opportunities that this country now has to forge a positive and exciting new relationship not just with the European Union but also with the rest of the world’.

Labour MP Gisela Stuart, who will chair the new group, also provocatively said that the Brexit vote was more significant than Mrs May becoming Prime Minister.

‘The referendum marked a more profound political change than a change of occupancy in Downing Street. It has forced us to acknowledge that people in large sections of the UK have lost faith in political parties and the Westminster elite,’ she said.

The Change Britain launch comes just days after Mrs May slapped down Mr Johnson by vetoing the idea of an Australian-style system for immigration, a policy which he has promoted.

Change Britain's aim is to ensure that Mrs May does not try to negotiate a form of ‘Brexit-lite’ involving compromises over immigration controls in exchange for greater access to the single market

The Prime Minister also delivered a rebuke to Brexit Secretary David Davis after he told the Commons on Monday it was ‘very improbable’ that the UK would remain a member of the single market if the country was to regain control of its borders. Her spokesman said Mr Davis was setting out ‘his opinion’, not Government policy.

The third Brexiteer, International Trade Secretary Liam Fox, was yesterday dealing with the backlash from his claim in a speech to activists on Thursday that Britain was ‘too lazy and too fat’ with businessmen preferring ‘golf on a Friday afternoon’ rather than contributing to the country’s prosperity.

Richard Reed, the founder of the Innocent Drinks group, criticised Dr Fox as a ‘terrible, terrible voice for British business’.