QUESTIONS have been asked about how the Prime Minister’s new chief of staff will balance the “24/7” role with also being a Cabinet minister and an MP, as Boris Johnson brought new faces into Downing Street following a swathe of resignations.

The Prime Minister announced on Saturday that Steve Barclay, the Chancellor of the Duchy of Lancaster, would become his chief of staff and take forward reforms to No 10.

But former holders of the job lined up to say they were unsure how Barclay would be able to undertake all his roles. Gavin Barwell, who was chief of staff to Theresa May, praised Barclay as “diligent, smart, insists on high standards and a nice guy to boot”. But the Tory peer said it “won’t be easy to combine being chief of staff with a minister and MP”.

The National: Gavin BarwellGavin Barwell

Nick Timothy, who was also chief of staff to May alongside Fiona Hill, tweeted: “Barclay is very talented, but not sure having a chief of staff who’s also a minister elsewhere can work.”

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Jonathan Powell, who held the role under Tony Blair, tweeted: “Does he resign as an MP? Or is he answerable to Parliament? I can think of no democracy where the chief of staff can also be in the legislature.

“I found being No 10 chief of staff a full-time job. Not sure how it could be combined with representing a constituency. And having to go to answer parliamentary questions about the PM would be tricky.”

The National: CALLS: Prime Minister Boris Johnson leaves 10 Downing Street. Photo: Jonathan Brady/PA Wire

Johnson previously insisted he was “making changes” to Downing Street and the Cabinet Office in the wake of the handling of the Partygate saga. This included creating an Office of the Prime Minister with a permanent secretary to lead No 10.

The Sunday Telegraph reported strategists Sir Lynton Crosby and David Canzini had also been providing Johnson with advice. Barclay, who is seen as a steady pair of hands, has been tasked with “integrating the new Office of the Prime Minister and the Cabinet Office”, Downing Street said.

Johnson also announced long-term ally Guto Harri, who worked with the him at City Hall when he was Mayor of London, would become his director of communications.

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Labour’s deputy leader Angela Rayner, who shadows Barclay, said: “The Prime Minister has clearly run out of serious people willing to serve under his chaotic and incompetent leadership, so now expects a Cabinet minister to be his chief of staff. This is a farce. Being No 10 chief of staff is a 24/7 role so if Steve Barclay is taking it on as his third job then Tory MPs and the public can have no confidence that the dysfunction in Downing Street will come to an end.”

The National: Angela RaynerAngela Rayner

The Institute for Government’s Dr Catherine Haddon suggested that if Barclay was staying in his Cabinet Office role, “this is not a chief of staff”. She said: “Either he’s a chief of staff and CDL (Chancellor of the Duchy of Lancaster) responsibilities will be neglected. Or he’s de facto deputy PM (despite Raab’s title) and you’re lacking a chief of staff.”

Labour MP Chris Bryant, who chairs the Commons Committee on Standards, tweeted: “I don’t understand how an MP can be a chief of staff at Drowning [sic] Street, either democratically, legally or logically.”

The PM will hope the changes are enough to win around wavering backbench Tory MPs who were considering over the weekend whether to submit letters of no confidence in Johnson to Sir Graham Brady.

If the chairman of the 1922 Committee receives 54 letters a vote of no confidence will be called. So far, 15 Conservatives have publicly called for Johnson to go, but not all have sent letters to Brady. Privately, the numbers are expected to be higher.

Culture Secretary Nadine Dorries launched a passionate defence of the Prime Minister, claiming that 97% of Tory MPs supported Johnson.

She also insisted Johnson told the truth “to the best of his knowledge” based on what he was told by his aides. The new roles in No 10 come after Johnson lost five aides within 24 hours, including long-term head of policy Munira Mirza, director of communications Jack Doyle, chief of staff Dan Rosenfield, and principal private secretary Martin Reynolds.