UPDATED 3PM

WORCESTER MP Robin Walker today throws his weight behind Theresa May as next Prime Minister - backing her to "unite the country".

The Conservative, who has spent the last two days locked in private discussions before making his mind up, has handed Mrs May a ringing endorsement by calling her "Prime Minister material".

It comes as Boris Johnson sensationally pulled out of the leadership race today, saying he could not provide the leadership or unity needed after an apparent fallout with Michael Gove.

The ballot for next Conservative leader closed at noon leaving Mrs May, 59, now odds-on to become Britain's first female PM since Margaret Thatcher.

There are five candidates alongside May and Gove including Work and Pensions Secretary Stephen Crabb, energy minister Andrea Leadsom, a key figure in the 'Leave' campaign, and outsider Liam Fox.

Mr Walker said: "Theresa can bring people together in the way absolutely nobody else can, she's got the clout.

"We're not just thinking about the party but more importantly the country, she's tough and can get what Britain needs - she's a cool, calm head in a crisis.

"I don't know if we're in a crisis now, but we don't want to see this 'challenge' get any worse, and she is the type of person to rise to the challenge.

"Her record of holding one of the great offices of state, the longest serving Home Secretary for a generation, makes this a very clear decision for me - she's a one nation Conservative."

West Worcestershire MP Harriett Baldwin has also backed Mrs May today, saying she is "the right person to go toe-to-toe with Angela Merkel".

She said: "The time for arguments about Remain and Leave is over.

"It's time to unite, deliver the Conservative manifesto and implement the negotiations to leave the EU.

"Theresa May is the right person to go toe-to-toe with Angela Merkel and other EU leaders in this important negotiation, because she's got a strong track record of negotiating and implementing.

"Being Home Secretary is one of the toughest jobs in Government. She’s done it for longer than anyone.

"She's carefully supervised our security services and changed rules that have kept us safe at home.

"She’s brought in reforms to immigration from outside the EU, she's reformed the police and delivered more accountability to local people.

"Crime has fallen and she's succeeded in some tough international negotiations, like sending Abu Qatada back to Jordan."

Mrs May's leadership bid was given a huge boost last night when a YouGov poll of 1,001 party members - who will make the final choice from two final candidates - gave Mrs May a 17-point lead.

We can also reveal how that grassroots support extends to Worcester Conservative Association, where its current President Andrew Grant and the three past or current chairs James Stanley, David Tibbutt and Lucy Hodgson are all backing Mrs May.

Mr Johnson's unexpected - and dramatic - announcement that he would not stand for Tory leader and therefore Prime Minister, positions he is long thought to have harboured ambitions for, has dramatically altered the race.

In an astonishing turn of events, Mr Johnson launched a press conference and said: "Having consulted colleagues and in view of the circumstances in Parliament, I have concluded that person cannot be me."

The five hopefuls will now get voted on by Tory MPs, with three eliminated per week, before the final two are placed on a shortlist for its membership.

A new Conservative leader will be in place on September 9 - and replace David Cameron in Downing Street.