Theresa May speech live: Prime Minister resigns and says she will stand down on June 7

British Prime Minister Theresa May reacts as she turns away after making a speech in the street outside 10 Downing Street in London, England, Friday, May 24, 2019. Theresa May says she'll quit as UK Conservative leader on June 7, sparking contest for Britain's next prime minister. (AP Photo/Alastair Grant)

Theresa May has announced she is to stand down as Prime Minister on 7 June following months of mounting pressure over her failure to deliver Brexit.

In a speech outside Downing Street, Mrs May said she had accepted that she had been unable to deliver Brexit and would stand down.

The final straw of her doomed premiership came when a last-gasp effort to win support for her Withdrawal Agreement Bill backfired spectacularly and it became obvious her Brexit deal was dead in the water.

Brexiteers within her own party were enraged by the concession of the offer of a potential second referendum and customs union arrangement announced on Tuesday. She also lost the support of many senior Cabinet members who made it clear her time was up.

Labour and the DUP also said they would not support the deal.

Andrea Leadsom dealt another blow when she quit as Commons leader on Wednesday evening saying she had lost confidence Mrs May would "deliver on the referendum result".

Mrs May delivered her speech this morning shortly after meeting the chairman of Tory backbenchers at 9am. The timing means a new Tory leader - and therefore Prime Minister - should be in place by the end of July.

Her announcement means she will still be in power for Donald Trump’s state visit on 3-5 June.

It also comes the day after European elections, in which the Tories are expected to perform disastrously.

Boris Johnson is the current favourite to replace Mrs May.

He has already confirmed he will stand, telling a business event “of course I’m going to go for it”.

However, he remains a Marmite figure in the Tory Party and faces significant opposition to succeeding Mrs May.

Theresa May is reaching the end of the road (Photo by Dan Kitwood/Getty Images)