Ten candidates have formally entered the crowded race to be the next prime minister, after securing the backing of eight fellow Conservative MPs.

The party announced that outsiders Rory Stewart, Andrea Leadsom, Esther McVey and Mark Harper had got to the starting line – scotching rumours that they would fail to be nominated.

But Sam Gyimah, the only contender who backs a Final Say referendum on Brexit, pulled out, saying he had run out of “time to build sufficient support”.

The list will be whittled down to just two by multiple votes of the 313 Conservative MPs by the end of the month, before the final choice is made by the 160,000 Tory members.

The new prime minister will be known by the “end of the week” beginning 22 July – leaving open the possibility that MPs will already be on their summer recess.

Put It To The People march: Best of The Independent’s pictures Show all 24 1 /24 Put It To The People march: Best of The Independent’s pictures Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent Put It To The People march: Best of The Independent’s pictures Put It To The People protest 23 March 2019 Angela Christofilou/The Independent Angela Christofilou/The Independent

Labour has threatened an immediate vote-of-no-confidence, with just three Tory switchers needed to defeat the winner and trigger a constitutional crisis.

There is pressure on Conservative MPs opposed to a no-deal Brexit not to support a new leader – such as Mr Johnson – adopting that policy.

The announcement, from the 1922 Committee of backbench Conservatives, came after a day of back-to-back leadership launches with Mr Hunt, Mr Gove, Mr Raab, Mr Hancock and Ms McVey setting out their stalls.

Mr Gove, the environment secretary, insisted he was still in the race to "win it" despite calls for him to withdraw over his cocaine admission.

Meanwhile, the campaign of Mr Hunt, the foreign secretary, was bolstered by the backing of two Cabinet ministers - influential Remain supporter Amber Rudd and prominent Brexiteer Penny Mordaunt.

Mr Hancock pledged to increase the national living wage to more than £10 an hour and said he would reduce taxes on working people “when we can afford it”.

Mr Raab spelled out his desire to break from the EU by 31 October, even without a deal if necessary, and called for a “generational change in leadership”.

Candidates need to win 5 per cent of votes (16 MPs) to stay in after the first ballot on Thursday and 10 per cent (32 MPs) to survive the second.

The plan was agreed to avoid protracted rounds of voting that threatened to derail the intention to install a replacement for Ms May by late July.