Scottish Conservative leader Ruth Davidson has revealed she is backing Home Secretary Theresa May to be the UK's next prime minister.

She described Mrs May as a "proper grown up", adding that she is "best placed to navigate the stormy waters ahead".

The Scottish Conservative leader announced her preferred candidate in the ballot to replace David Cameron after the contest was reduced to two MPs.

Michael Gove was eliminated after securing 46 votes in the second round ballot, leaving just Mrs May, the front-runner with 199 votes, and energy minister Andrea Leadsom, who was backed by 84 MPs.

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Tory members across the UK will now decide whether Mrs May - who has already been backed by Scottish Secretary David Mundell - or Mrs Leadsom will be their next leader, and also the UK's prime minister.

Like the Home Secretary, Ms Davidson backed the Remain campaign in the run up to the EU referendum.

The Scottish Conservative leader said: "Serious times call for serious people and Theresa is a proper grown up who will assess all the evidence before making a decision.

"I trust her in the tough negotiations ahead to be able to go eyeball to eyeball with (German Chancellor) Angela Merkel, and not blink."

She added: "It is important that the new prime minister is alive to the threats to our union that the SNP will try to engineer. And it is no surprise that those in leadership positions in the Conservative Party in Scotland - myself in Holyrood, Annabel Goldie in the House of Lords, David Mundell in the Commons and our MEP Ian Duncan - are all agreed that the person most able to protect Scotland's place in the United Kingdom is Theresa May.

"As the leader of the party in Scotland, I have a responsibility to take the selection of our next UK leader - and prime minister - seriously indeed. I do. And that's why I can say without hesitation that I believe Theresa May is best placed to navigate the stormy waters ahead."

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The leadership contest was triggered when Mr Cameron announced he was stepping down in the wake of June's vote to leave the European Union. The new prime minister will be known after the postal ballot of Conservative Party members closes on September 9.

Ms Davidson, who got engaged to her long-term partner Jen Wilson in May, said she would invite the next prime minister to her marriage - even if it was Mrs Leadsom, who has expressed concerns about same-sex weddings.

Mrs Leadsom told ITV News: "I would have preferred for civil partnerships to be available to heterosexual and gay couples and for marriage to have remained as a Christian service that was for men and women who wanted to commit in the eyes of God."

Mrs Leadsom then claimed she "absolutely" supports gay marriage.

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Ms Davidson told BBC Two's Newsnight: "I don't know Andrea Leadsom very well. I think she said it was something to do with her faith.

"As a woman of faith myself, who has talked openly about her Christianity and some of the difficulties I have had in my past having to reconcile my faith and my sexuality, I know it can take some time for some people to do that.

"I'm very pleased that Theresa May was instrumental in bringing forward same-sex marriage, it's something that I supported going forwards. Whoever becomes prime minister, they will get an invitation to my wedding when it happens."