NO 10 has refused to deny reports that Boris Johnson is considering setting up a charity to pay for the refurbishment of his official Downing St flat after it was suggested he was concerned about his fiancée, Carrie Symonds’s expensive tastes.

Reports point to the prospect that the scheme for the refurbishment of the flat above No 11 – based on one used by the White House – could be funded by wealthy Tory benefactors.

However, any such move has raised questions over possible conflicts of interest, offering a potential backdoor way of providing a financial benefit to the Prime Minister.

Allegra Stratton, his Press Secretary, described the reports as “speculation” while his spokesman referred journalists to the Cabinet Office annual report and accounts, which have yet to be published for the relevant period.

“That is where we set out the details of what has happened,” the spokesman declared. “Downing Street is a working building as has been the case under successive administrations, refurbishment and maintenance are made periodically.”

Ms Stratton added: “Downing Street is maintained to appropriate standards for the Grade I and II listed building that it is. The Cabinet Office sits in oversight of that. As things stand there is already a process in place for maintaining it to the right standard.”

The PM is reported to have complained that the cost of refurbishment – which is now said to be complete – was “totally out of control” and had run to “over a hundred grand”.

He is said to have told one minister that he was particularly concerned about the cost of the wallpaper chosen by Ms Symonds, saying she appeared to have ordered “gold wall coverings”.

Earlier, Mr Johnson denied that members of his No 10 team were at war with each other, following a series of hostile press briefings aimed at his fiancee.

The PM insisted his Downing Street operation was a “nest of singing birds” and that they were “mono-maniacally” focused on dealing with the Covid pandemic.

It follows the dramatic departure last year of Mr Johnson’s chief adviser Dominic Cummings after he reportedly clashed with Ms Symonds in a bitter No 10 power struggle and the swift exit last month of Oliver Lewis from the PM’s Union Unit following another supposed clash with the PM’s partner.