Former Tory chief whip Gavin Williamson has been appointed as Theresa May's defence secretary.
The appointment comes after Michael Fallon was forced to resign his position last night following accusations of sexual misconduct.
As chief whip, Williamson played a crucial role in ensuring the government pushed through votes with its wafer-thin majority.
Julian Smith, MP for Skipton and Ripon, has been promoted to the position of chief whip, having previously acted as deputy chief whip. Tatton MP Esther McVey, who was work and pensions minister for three years, has been appointed as deputy chief whip.
Williamson's sudden elevation into a cabinet role will be controversial with many of his parliamentary colleagues.
Sarah Wollaston, Conservative MP for Totnes and chair of the Health Select Committee, tweeted: "There are times when offered a job that it would be better to advise that another would be more experienced and suited to the role."
Menzies Campbell, Liberal Democrat defence spokesperson, said:
The surprise new Defence Secretary has a mountain to climb, and quickly...Gavin Williamson’s first phone call should be to the chancellor of the exchequer urging him not to propose any reduction in defence spending in the coming budget.