Theresa May faced a blunt threat from Brexiteers today as a senior MP openly questioned whether she 'really wants to leave' the EU.
Jacob Rees-Mogg launched a savage attack on the Prime Minister for 'kowtowing' to Brussels in negotiations.
He accused the government of 'preparing for failure' by making concessions over staying tied to the EU customs union.
He also challenged Mrs May over fears about Brexit triggering the break-up of the union, saying if she believes the people of Northern Ireland want to merge with the Republic she has a duty to call a referendum.
Jacob Rees-Mogg (pictured in London today) has launched a savage attack on the Prime Minister for 'kowtowing' to Brussels in negotiations
Mrs May has been fighting to defuse Eurosceptic fury at 'backstop' plans to keep Britain tied to the customs union to avoid a hard Irish border.
The Prime Minister said yesterday that the proposal was a last resort and would have to be for a 'limited time' as she denied caving into Brussels.
The Irish border has become the critical issue in Brexit negotiations, with the UK and the EU engaged in bitter wrangling over how to avoid imposing 'hard' customs checks.
Brussels has dismissed the government's options of either a customs partnership or a 'Maximum Facilitation' technological solution.
A divorce deal struck by Mrs May before Christmas included a backstop that if no other solutions were found to avoid a hard border, the UK would stay aligned to EU rules in key areas.
However, a legal text of the document