Senior Tories have lined up behind Theresa May's leadership bid as rival Michael Gove prepared to set out his case for becoming prime minister.
Cabinet colleagues Michael Fallon and Patrick McLoughlin declared their backing for the Home Secretary's campaign as the candidates to replace David Cameron as Tory leader and premier jostled for support.
Justice Secretary Gove will set out his case for the leadership in a speech on Friday after his last-minute decision to enter the race effectively torpedoed Brexit campaign ally Boris Johnson's hopes of entering Number 10.
Setting out his support for the Home Secretary, Fallon said: "As Defence Secretary, I've worked closely with Theresa on security and she is the right person to steer Britain through the serious challenges we now face.
"Theresa is the best person to lead our exit from the EU so that we reduce immigration and regain sovereignty while protecting our hard-won economic growth.
"She has the track record, the temperament and the commitment to unite both the party and the country behind a clear plan for our future."
Transport Secretary McLoughlin, writing in The Sun, said May would be able to do the required deals in Brussels as the UK negotiated its exit from the European Union.
Suggesting May had "the 'it' factor", he said: "We know that the next prime minister needs to forge a deal from the EU as we shape our brighter future in the rest of the world. And her track record shows that when Theresa arrives in Brussels, Europe's bosses sit up and listen."
Cabinet Office minister Matt Hancock pledged his support to May, telling BBC Two's Newsnight: "I think we need somebody with a steady hand on the tiller who has got proven leadership credentials."
Johnson's shock decision not to stand catapulted May into pole position, with Gove positioning himself as the leading Brexiteer in a field of five contenders also including Work and Pensions Secretary Stephen Crabb, energy minister Andrea Leadsom and former defence secretary Liam Fox.
Gove will set out further details of his plans for the premiership in a speech in Westminster.
He revealed he decided to run late on Wednesday night after coming to the conclusion that fellow Vote Leave campaigner Johnson could not provide the unity or the leadership to take Britain out of the EU.
Gove said: "In the last four days I had a chance to see up close and personal how Boris dealt with some of the decisions we needed to make in order to take this country forward.
"During that period I had hoped that Boris would rise to the occasion because inevitably when you have a leadership election, people are tested, questions are asked of them, tests are set.
"Boris has formidable qualities but I saw him seek to meet and not pass those tests. I also thought ultimately, can I recommend to my friends that this person is right to be prime minister?"
Gove has repeatedly denied having leadership ambitions in the past and his late intervention in the race drew criticism from supporters of Johnson.
MP Kwasi Kwarteng, who has now switched to back May, accused the Justice Secretary of indulging in "student politics" while Jake Berry said in a now-deleted tweet: "There is a very deep pit reserved in hell for such as he."
May also won the support of the Daily Mail newspaper and appeared to have taken an early lead in the crucial race to win the allegiance of MPs to secure her place on the shortlist of two that will be voted on by party members.