DOWNING Street is in chaos this morning, with Boris Johnson’s closest advisors at each other’s throats.

That's despite the UK’s coronavirus death rate passing the grim milestone of 50,000 fatalities and the looming threat of a No-Deal Brexit.

Last night, Lee Cain announced he would step down as director of communications, after Tory ministers and advisers including Johnson’s partner blocked his planned promotion to chief of staff.

That resignation led to rumours that Dominic Cummings, the Prime Minister’s right-hand man, could also quit. 

The two men were close allies having worked together on the Vote Leave campaign.

Reports suggest that Johnson offered the new chief of staff position to Cain last week. That followed claims the ex-Mirror journalist had been mulling over quitting No 10 in part because of clashes with Allegra Stratton – the new Downing Street spokeswoman, who is due to host the new televised press conferences from January.

Cain isn’t universally liked and a number of MPs and special advisers protested the possible promotion, which would have made him one of the most powerful men in the country. 

Johnson’s fiance, Carrie Symonds – who is a former head of communications for the Tories – also opposed Cain’s appointment.

Sir Charles Walker, vice-chairman of the 1922 committee of backbench Conservative MPs, told BBC Radio 4’s Today programme that the resignation was a good thing: “I think there has been unhappiness about the No 10 operation for some time. Members of parliament have felt excluded from the decision-making process, and that’s no secret.

“The real opportunity here is for the chief of staff position to be filled by someone who has good links with the Conservative Party and its representation in the House of Commons.”

Jake Berry, MP for Rossendale and Darwen, told ITV’s Good Morning Britain that the Prime Minister was stamping his “Johnsonian authority across the No 10 operation.

“The departure of Lee Cain does show, I think, that the Prime Minister is taking back control of his government. As we go past that grim milestone of 50,000 deaths from this appalling disease, it’s high time that there was a bit of a change of guard in No 10.

However, allies of Cain said he had been acting as de facto chief of staff for some time and had “absolute loyalty” to the Prime Minister. 

Cain will leave No 10 at the end of the year.

In a statement he said he had made the decision “after careful consideration”.

“It has been a privilege to work as an adviser for Mr Johnson for the last three years – being part of a team that helped him win the Tory leadership contest, secure the largest Conservative majority for three decades – and it was an honour to be asked to serve as the prime minister’s chief of staff,” he said.

“I would like to thank all the team at No 10 – including the many unsung and incredibly talented civil servants – for their hard work and support during the last 18 months.

“And most of all I would like to thank the Prime Minister for his loyalty and leadership. I have no doubt that under his premiership the country will deliver on the promises made in the 2019 election campaign and build back better from the coronavirus pandemic.”

Johnson added: “I want to thank Lee for his extraordinary service to the government over the last four years.

“He has been a true ally and friend and I am very glad that he will remain director of communications until the new year and to help restructure the operation. He will be much missed.”

James Slack, the Prime Minister’s official spokesman and the former political editor of the Daily Mail, is set to take over as director of communications.

SNP Westminster Deputy Leader Kirsten Oswald MP called the civil war, "shameful". 

She said: “The UK faces a growing Tory unemployment crisis, a devastating global pandemic, as well as the looming end of the Brexit transition period. It is a shameful distraction that senior members of the Tory government are wasting time fighting among themselves – when people’s lives and livelihoods are under threat.

“The fact that Boris Johnson’s most senior political advisers are busy waging a Tory civil war over their highly paid, taxpayer-funded positions, while the UK is hit by the worst health and economic crisis in decades, tells you everything you need to know about this arrogant, incompetent and self-serving Tory government. It’s a total shambles - they would be ashamed if they had a shred of decency."

Oswald added: “In contrast, Nicola Sturgeon’s SNP Scottish Government is getting on with the job at hand, and tackling coronavirus with the seriousness it deserves. It’s no wonder that a growing majority of people in Scotland want nothing more to do with the broken Westminster system.”

The Labour leader, Sir Keir Starmer, called the situation “pathetic”. He said: “Millions of people will be waking up this morning, scratching their heads, saying what on earth is going on? We’re in the middle of a pandemic, we’re all worried about our health and our families, we’re all worried about our jobs, and this lot are squabbling behind the door of No 10. Pull yourselves together, focus on the job in hand.”