What is the row between Boris Johnson and Dominic Cummings all about?

A behind-the-scenes feud between Boris Johnson and his former aide Dominic Cummings has exploded publicly in recent days.

Here we look at what has been going on:

– What sparked the Downing Street briefing war?

Late on Thursday night, three newspapers carried the explosive claim, attributed to No 10 sources – although some reports have suggested it was Boris Johnson himself who picked up the phone to editors – that Dominic Cummings was behind a series of leaks targeting the Prime Minister.

Mr Cummings was also fingered as the likely culprit in the leaking of messages between Mr Johnson and the Saudi Crown Prince, Mohammed bin Salman, and suspicions have also been raised by a series of disclosures about the funding for renovations of the Prime Minister’s Downing Street flat.

– What was Dominic Cummings’s response?

If revenge is a dish best served cold, Mr Cummings appears to be offering something straight out of the freezer.

In a blog post responding to the accusations, he denied leaking the Dyson texts but went on to make a series of incendiary claims about Mr Johnson’s conduct.

Mr Cummings also claimed he told Mr Johnson that “plans to have donors secretly pay for the renovation” of the Downing Street flat “were unethical, foolish, possibly illegal and almost certainly broke the rules on proper disclosure of political donations”.

The Government has revealed that Mr Johnson has paid the bill for the renovations himself, although Labour has demanded a full inquiry.

– Anything else?

The leaks have continued, with ministers strongly denying claims that Mr Johnson said “no more f****** lockdowns – let the bodies pile high in their thousands” after ordering the second shutdown in October.

Mr Johnson denied making the comment and stressed that lockdowns had been successful in driving down cases.

Downing Street is braced for further hostile fire from Mr Cummings when he appears before a Commons select committee on May 26.

– Does any of this really matter?

Mr Cummings – someone who was at Mr Johnson’s side during the Vote Leave campaign and in No 10 – now believes the Prime Minister has fallen “below the standards of competence and integrity the country deserves”.

Whether this can be simply shrugged off as a bitter ex-employee hitting out at his former boss remains to be seen, certainly that appears to be No 10’s strategy so far.

But the row, which follows hard on the heels of questions about David Cameron’s lobbying of former colleagues, has been seized on by Labour in the run-up to the May 6 elections as a sign the Government is slipping into a “mire of sleaze”.

Support for the Tories fell five points in a month according to an Ipsos Mori poll carried out in the days before the Cummings allegations, although at 40% the Conservatives still held a three-point lead over Labour.