Tom Tugendhat became the first to officially announce his bid to become the new prime minister - a day after Boris Johnson said he would stand down.
The MP for Tonbridge and Malling had previously made no secret of his ambition to lead the country, announcing back in January that he would stand should Mr Johnson resign.
Writing in The Daily Telegraph, the former soldier said: “I have served before – in the military, and now in Parliament. Now I hope to answer the call once again as prime minister.”
He is now down to the final six candidates in the race to be the leader of the Conservative party - although he came last out of the successful candidates in the most recent ballot, with 37 votes.
Who is Tom Tugendhat?
The 49-year-old Conservative was elected as the Member of Parliament for Tonbridge and Malling, a safe Conservative seat in Kent, at the 2015 general election.
A Remainer in 2016, the former soldier has been a trenchant critic of Mr Johnson – a stance that would appear to have cost him any chance of ministerial preferment under the current leadership.
He has been the Chair of the Foreign Affairs Committee since 2017.
Mr Tugendhat served with the Royal Marines in Iraq when war broke out in 2003. He was was mobilised as an Arabic-speaking intelligence officer.
He also served in Afghanistan when his Royal Marines unit was deployed to Helmand province. He served there for two years for which he received an MBE, and came off his last patrol in 2009.
He was particularly critical of Mr Johnson's withdrawal from Afghanistan, describing the fall of Kabul as Britain's "biggest foreign policy disaster since Suez".
He has also served as the military assistant to the Chief of the Defence Staff.
Mr Tugendhat is the son of Sir Michael Tugendhat, a High Court judge, and his French wife, Blandine de Loisne.
He got engaged to French judge and senior civil servant Anissia in 2013. They married a few months later and have two children.
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