Gavin Williamson appointed as new defence secretary
Sir Michael Fallon resigned from the cabinet amid claims of inappropriate behaviour.
Chief Whip Gavin Williamson has been appointed new defence secretary, Downing Street has said.
It follows the shock resignation of Sir Michael Fallon last night.
Sir Michael stepped down after it emerged he repeatedly put his hand on a female journalist's knee at a dinner in 2002.
He apologised for his behaviour saying it had "fallen below the standards required" for his role.
Sir Michael's resignation has prompted speculation others may follow suit after it emerged there was a list of MPs accused of inappropriate behaviour circulating.
Mr Williamson, who was the Government's chief whip before this appointment, will replace him in the job.
He has never held ministerial office before and did not speak to reporters as he left Number 10.
Who is Gavin Williamson?
Gavin Williamson got his big break when David Cameron made him his parliamentary private secretary from 2013 to 2016.
When Cameron resigned, Williamson backed Theresa May - who rewarded him by promoting him to her Cabinet as Chief Whip.
His promotion to defence secretary is the first time the 41-year-old has held ministerial office.
Born in Scarborough, North Yorkshire, to Labour-supporting parents, Williamson did not enter Parliament until 2010 when he became MP for South Staffordshire.
He is known in Westminster for keeping a pet tarantula named Cronus in a glass box on his desk, which is said to have provided added menace when dealing with errant MPs in his role as Mrs May's enforcer.
"You have to look at all different ways to persuade people to vote with the Government and it's great to have Cronus as part of the team," he said on his appointment as chief whip, with responsibility for maintaining discipline among Tory MPs.
Married with two daughters, his background is in manufacturing and design at a pottery in Staffordshire and an architectural design company.
He was awarded a CBE in Mr Cameron's resignation honours for political and public service.