Work and Pensions Secretary Stephen Crabb has dropped out of the race for the leadership of the Conservative Party and backed frontrunner Theresa May.
Crabb quit the race after coming fourth in the first round of the contest after securing 34 votes compared to May's 165.
The Work and Pensions Secretary said he was now backing May, insisting "there is only one candidate" to unite the Tories and form a "cohesive and strong" government.
Michael Gove, who finished in third place on 48 votes behind Andrea Leadsom with 66, vowed to fight on after Liam Fox was eliminated.
Earlier, Crabb told BBC News: "I entered this leadership race with the overriding goal of putting two themes at the heart of the debate - unity for our divided nation and opportunity to tackle disadvantage in particular.
"And I've been overwhelmed by the support I've received from colleagues - those who voted for me today but those who didn't as well, but who made the point to me that they share my one nation vision and they want that one nation vision to be at the heart of the next Conservative government.
"I think tonight we need to recognise that there is only one candidate in a position to unite our party and to form a cohesive and strong government, which our country needs at this time.
"I mean this is a really, really serious moment for this country and so I've taken the decision that I won't put my name forward to the next round of voting but instead of that I'll be lending my wholehearted support to Theresa May, who is overwhelmingly in the best position to be the next prime minister and the leader of the Conservative Party."
The two candidates who top the final round of MPs' votes will go forward to a postal ballot of party members to select a new Conservative leader - and prime minister - in a contest due to end on September 9.