Boris Johnson’s senior adviser Dominic Cummings has let it be known he is leaving Downing Street.
The Prime Minister’s controversial aide is expected to step down from his role by the end of the year,
Here, the PA news agency takes a look at why he is going.
– What happened?
Mr Cummings says he always intended to depart at the end of the year but all the signs are he is leaving after losing out in a power struggle among the Prime Minister’s inner circle.
He wanted his close ally Lee Cain – the No 10 director of communications – to be installed as Mr Johnson’s chief of staff, thereby strengthening his own grip on the Downing Street operation.
But the proposed move infuriated many senior Tories – and, it is said, the Prime Minister’s fiancee Carrie Symonds – who were alarmed at the prospect of Mr Cummings extending his influence even further.
When it failed to work out, Mr Cain – who feared he was being sidelined with the appointment of a new press secretary – announced he was quitting.
– What did Mr Cummings do?
Mr Cummings says reports he threatened to resign on the spot are an “invention” but he was clearly very unhappy at what happened.
Within a little over 24 hours he was telling the BBC he would be going, too.
– Why are people making such a fuss over an adviser leaving?
Mr Cummings was regarded as being more powerful than most ministers, exerting control over the Government’s agenda and demanding iron discipline from the army of Whitehall special advisers.
As Vote Leave campaign director he is regarded as the mastermind behind the 2016 Brexit referendum vote and is credited with playing a key role in last year’s general election victory.
But his abrasive manner and open contempt for MPs and officials earned him many enemies in Westminster, who will not be sorry to see him go.
– What effect will his departure have?
It is not clear – although some at Westminster are predicting it will lead to a less confrontational style of government with a greater focus on issues such as climate change and building bridges with the devolved administrations.
Unhappy Tory MPs, who have felt ignored by No 10 since the election, will hope Downing Street will begin including them.
Others expect there will be less inclination on the part of the Government to pick fights across a range of institutions – from the BBC and the media to the judiciary.
Whether it works out that way remains to be seen.