One of the prime minister’s most senior advisers has been suspended, the BBC understands.
Jason Stein, a special adviser to Liz Truss, is to face a formal investigation by the Propriety and Ethics Team, which is responsible for standards across government.
It follows some anger from Conservative backbench MPs about briefings from No 10 sources over the weekend.
Mr Stein has not yet responded to requests for comment from the BBC.
Warning: strong language used further down in this article
He previously worked for Ms Truss when she was chief secretary to the Treasury before he became a special advisor to Amber Rudd.
He also worked for Ms Truss during her Tory leadership campaign.
Asked about the suspension, Ms Truss’s spokesman refused to refer to Mr Stein by name, but told reporters: “The prime minister has made it very clear that some of the briefings are completely unacceptable and must stop.”
This was a reference to briefings to newspapers from those around her who can speak on her behalf, which contained strong language.
Over the weekend, the Sunday Times reported that Ms Truss was of the view that the former Chancellor and Health Secretary Sajid Javid was “shit”.
It was expected that Mr Javid would raise the matter at Prime Minister’s Questions, but I understand both he and Mr Stein were told just before midday of the special adviser’s suspension.
Mr Javid had been seen by some as a possible replacement for Kwasi Kwarteng as chancellor, but Jeremy Hunt was picked instead.
Asked if Mr Stein had offered his resignation, a Conservative source said “that is not my understanding”.
Before joining Downing Street, Jason Stein used to work as a communications adviser to Prince Andrew.
It’s understood he left as an employee of the prince when his advice not to do an interview with [BBC Newsnight’s] Emily Maitlis was ignored.