Is Theresa May about to resign, and what happens if she does - or doesn't?

Benjamin Kentish

Theresa May's days in Downing Street are coming to a rapid end.

Speculation is mounting that the prime minister will announce her resignation on Friday, amid mounting pressure to quit from within her cabinet and her party.

She angered many Conservatives on Tuesday by making a fresh offer on Brexit in a final bid to get her deal through parliament, including compromises on a customs union and a second referendum.

That prompted Andrea Leadsom, the leader of the Commons, to resign, while senior cabinet ministers demanded that Ms May abandon the new plan, and many MPs stepped up their calls for her to go.

Ms May is due to meet Sir Graham Brady, chair of the 1922 Committee that represents Tory MPs, on Friday. He is likely to re-iterate MPs' demands that the prime minister set a date for her departure.

Will Theresa May resign?

She is expected to announce a resignation date of 10 June after meeting Sir Graham on Friday morning.

Ms May has so far rejected all calls to step down before she delivers Brexit.

She has vowed to resign if MPs approve her exit deal, but has not said when she will leave office if she is unable to secure approval for her plan.

With there being little prospect of the deal passing the Commons, she has come under mounting pressure to set a timetable for her departure regardless of what happens in relation to Brexit.

Reports suggest the prime minister will now agree to announce a timeframe for her resignation, with the leadership contest to succeed her expected to begin on 10 June.

What if she refuses to go?

If Ms May refuses to step down, or at the very least to set a date for her departure, she faces being forced from office either by her cabinet or by Conservative MPs.

Both have grown increasingly frustrated at her handling of Brexit and there are now very few Tory MPs who believe she should stay in office beyond the next few weeks.

Under current Conservative Party rules, a vote of no confidence in the leader cannot be held until December - a year after the last one, which Ms May won. However, the executive of the 1922 Committee has come under pressure to change this.

The executive is said to have already held a secret ballot on whether to change the rules to allow another vote of confidence in Ms May within days. These votes will reportedly be counted on Friday if Ms May refuses to set a date for her departure when she meets Sir Graham.

If the rules are amended, 15 per cent of Tory MPs - 48 MPs - would need to request a confidence vote for one to take place. This threshold is all but certain to be met.

The vote itself is decided by a simple majority. While Ms May comfortably saw off the bid to oust her last December, there is now believed to be a majority among Conservative MPs for her to be forced from office.

Government ministers have voiced strong objections to her latest Brexit offer, outlined in a draft of the Withdrawal Agreement Bill, which enshrines the deal in law. While they have stopped short of publicly calling on the prime minister to go, in private most believe she has no chance of getting the bill through parliament and that her exit from No10 is now imminent.

What will happen when she resigns or is forced out?

Whether she resigns on her own accord or is forced out in a no confidence vote, the end of Ms May's premiership will trigger a Conservative leadership contest.

The other big question is whether she will stay in office while the leadership contest to succeed her takes place, or whether she will step down immediately and her deputy, David Lidington, step in as interim prime minister.

Her predecessor, David Cameron, stayed on until Ms May was chosen to replace him it is widely expected that she will also stay in place during the leadership contest. This would give her time to pass legislation on her pet projects - and possibly some of the less contentious parts of her Brexit deal - in order to secure some form of legacy.

But the length of the leadership contest will be decided by the 1922 Committee.

How does a Tory leadership contest work?

Conservative Party rules are very vague about how the leadership contest will work will work.

The timeframe is for the 1922 Committee executive to decide.

All the rules state is that Conservative MPs will whittle down the number of candidates, of which there are expected to be many, to two. These will then be put to all party members in a ballot.

Many Tory MPs want the process completed before parliament's summer break beings in mid-July. This would require a short, sharp leadership election lasting around a month. If the 1922 Committee opts for a longer contest, it would be expected that the new leader would be in place in time for the Conservatives' annual conference at the end of September.

What does it mean for Brexit?

Theresa May's deal is dead on arrival in the Commons - so much so that even if she is still in office when it is due to be debated in early June, she may not bother to put it to a vote.

Even many Tory MPs who voted for it last time around, when it was defeated by 58 votes, say they will not do so again.

It is now all but certain that Theresa May cannot deliver Brexit.

What this means for Britain's departure from the EU depends on who takes over as prime minister.

If, as many expect, the next leader is a Brexiteer such as Boris Johnson or Dominic Raab, they will have to decide whether to try to renegotiate the deal or leave without a deal on 31 October.

The candidates have been coy about their intentions so far and the fate of Brexit will likely become clear only during the leadership contest. All that seems certain is that Theresa May will not be the prime minister when Britain leaves the EU - if indeed it leaves at all.