A married former cabinet minister has become the first Tory MP to face the party's new disciplinary procedures following a Telegraph investigation into his conduct.

A Downing Street source said that Stephen Crabb had been referred for investigation in line with a behavioural code launched by the party on Friday.

The disclosure comes after Mr Crabb, a devout Christian who stood for the Conservative leadership in 2016, admitted saying "some pretty outrageous things" to a young woman he had earlier interviewed for a junior role in his parliamentary office, and that the messages "basically amount to unfaithfulness".

A friend of the woman said they saw messages in which the father-of-two "said he wanted to have sex with her".

Mr Crabb said that the pair later met on "several occasions" for drinks and that the messages were sent "from both sides" with the knowledge that "nothing like that was actually going to happen between us."

But the 44-year-old faced claims of an "abuse of power", with Jess Phillips, a Labour MP, describing his behaviour as "sickening".

It is understood that the Conservatives' investigation was opened after an "internal" referral by Julian Smith, the new Chief Whip, rather than a complaint by the woman concerned. Mr Smith telephoned Mr Crabb on Friday night to notify him of the referral and was told that the MP would "fully cooperate" with the inquiry.