Theresa May faced claims from the SNP that she had misled parliament

A group of Labour and Tory MPs are attempting to take control of the Brexit process if Theresa May’s deal is voted down next week.

The move would be likely to result in a softer version of Brexit, with senior Conservatives claiming that there is a Commons majority for a permanent Norway-style customs deal.

With the prime minister widely expected in Westminster to lose the vote on her deal on Tuesday, rival camps are jostling to be in position when she is forced to scramble together a Plan B.

Cabinet ministers have begun discussing the idea of cross-party co-operation in the hope of bouncing Mrs May into accepting a softer Brexit deal next week. “It’s true that senior ministers are sounding people out on what