Boris Johnson will be the final judge of any investigation into whether he has breached the ministerial code, Downing Street has confirmed.
The prime minister faces claims he broke official rules over the funding of his Downing Street flat refurbishment.
The elections watchdog launched its own probe on Wednesday after No.10 refused to say whether Johnson sought an initial loan from the Conservative Party to cover renovations to his residence in No. 11, which he shares with partner Carrie Symonds and their baby son Wilfred.
Amid mounting allegations of “Tory sleaze”, including texts Johnson exchanged with billionaire businessman James Dyson about tax policy, the PM this week appointed Lord Geidt as the government’s new independent adviser on ministerial interests.
The post had been vacant since Alex Allan resigned after Johnson chose not to sack home secretary Priti Patel after a civil service probe found her guilty of bullying.
But Geidt will have no power to launch investigations into Johnson’s top team and the PM will remain as the “ultimate arbiter” of whether he or any other minister has breached the ministerial code.
The code governs ministers’ conduct and Geidt is expected to produce an annual report on their personal and financial interests, to ensure proper standards are upheld.
The prime minister’s official spokesman said Johnson is retaining control of the process as he has concerns an independent adviser with powers to launch probes could be drawn into an investigation with “trivial or vexatious complaints”.
“So he will remain the ultimate arbiter of this,” he said.
Asked if that means the prime minister could reject any findings on himself, the spokesman said: “The prime minister will remain the ultimate arbiter of this, yep.”
Pressed further on whether Johnson could overrule Geidt on any sanctions he recommended for ministers if they fell foul of the code, the spokesman said: “The prime minister, as has always been the case, remains the ultimate arbiter of the code and draws conclusions from it. That rightly remains with the prime minister.”
It comes as the Electoral Commission launched an investigation into the £200,000 flat makeover on Wednesday, saying in a statement it was satisfied that “there are reasonable grounds to suspect that an offence or offences may have occurred”.
Prime ministers get a budget of up to £30,000 per year to renovate their residency at Downing Street, but reports have suggested Johnson has spent up to £200,000.
Former aide Dominic Cummings accused him of wanting Tory donors to “secretly pay” for the renovations in a “possibly illegal” move.
A No.10 spokesperson has said that the costs “have been met by the prime minister personally” and that party funds “are not being used for this”.
Downing Street has said Johnson will be “happy to assist” if the Electoral Commission asks for any information from him during its investigation.
Asked if Johnson is willing to be questioned in person, the PM’s spokesperson: “This is a matter for the Conservative Party as a political party and CCHQ have said they will continue to work constructively with the Electoral Commission on this matter.
“They will provide all necessary information to assist the commission.
“The prime minister hasn’t been asked for any information but he and the government will of course be happy to assist if asked.”
Labour leader Keir Starmer pressed Johnson over the flat claims in the Commons on Wednesday.
Johnson has continued to insist he has paid for it personally, but refused to make clear whether he had been offered a loan from a donor.
Starmer said: “Who initially – and prime minister, initially is the key word here – who initially paid for the redecoration of his Downing Street flat?”
Johnson replied: “As for the latest stuff that he is bringing up, he should know that I have paid for Downing Street refurbishment personally.
“And I contrast it … any further declaration that I have to make, if any, I will be advised upon by (the independent adviser on ministers’ interests) Lord Geidt.”
