Theresa May will resign as Tory leader tomorrow but won’t step down as Prime Minister until she is certain the person replacing her will “command the confidence of the House”. This could prove especially tricky if a divisive, hardline Brexiteer like Boris Johnson or Dominic Raab wins the Tory leadership race. A controversial winner could fail to secure the support of soft Brexit or Remainer Tory MPs, or the DUP. Related articles Brexit LIVE: Labour face WIPE OUT in Peterborough LABOUR CRISIS: Now TWO-THIRDS want vote on Tom Watson’s future This means the new leader will not be Prime Minister of the country until he or she has the chance the ensure its confidence and supply deal with the DUP still stands and to secure the support of rival MPs. Mrs May’s spokesman told the Guardian she would not hand over the keys to Number 10 until she can “say to the Queen that she is stepping aside and believes that someone else can command the confidence of the House”. This means Mrs May’s successor as Tory leader could avoid facing an immediate no confidence vote in the Commons as ministers consider sending MPs home early for their summer break. READ MORE: Brexit live Theresa May will not resign as PM until she has confidence in her successor (Image: GETTY ) Theresa May could delay her resignation (Image: EPA ) Theresa May will resign as Tory leader tomorrow but won’t step down as Prime Minister until she is certain the person replacing her will 'command the confidence of the House' When Tory MP Peter Bone pressed Commons Leader Mel Stride to confirm the new party leader would face Parliament before the recess, he suggested the answer was “no, not necessarily”, given the uncertainty over when the leadership contest will conclude and the exact dates of recess. But Mr Stride said he was “confident” the Conservative Party’s confidence-and-supply agreement with the DUP will not be affected by the election of a new leader. The Conservative Party will not say exactly when the winner of their leadership contest will be announced - other than that it will be in the week of July 22. Labour sources believe the government is plotting to start recess as early as July 19. Related articles Andrew Neil warns of CONSTITUTIONAL CRISIS if this Brexit plan pursued No deal? NO PROBLEM! Britain will take hard Brexit ‘in our stride’ Theresa May resign: Boris Johnson is vying to become Tory leader (Image: REUTERS ) A House of Commons report ‘The Role of Parliament in the UK Constitution Interim’ explained: “The Prime Minister is under a duty not to resign unless and until it is clear another person commands the confidence of the House. “It is also clear that in the event that it becomes apparent that another person could command the confidence of the House the Prime Minister would be expected to resign. “Not to resign in such a circumstance would risk drawing the Sovereign in to the political process, something the Cabinet Manual is very clear should not occur.”All rights reserved for this news site express.co.uk and under his responsibility