Ministers are preparing for an early general election after Theresa May saw the first Conservative MP resign in protest at her handling of Brexit.

The prospect of the Prime Minister being forced to call a national vote in order to be able to deliver Brexit is now being “openly discussed” by Government ministers, senior sources said.

It came after Stephen Phillips, the Leave supporting MP for Sleaford and North Hykeham, triggered a by-election, saying that he had "irreconcilable policy differences with the current Government".

It prompted fears that Europhile Tories who oppose Brexit could follow him and trigger their own by-elections to pile further pressure on Mrs May.