How Boris Johnson funded a refurbishment of his Downing Street flat will be investigated by the elections watchdog, it has been confirmed. 

The Electoral Commission has said it is satisfied that “there are reasonable grounds to suspect that an offence or offences may have occurred”.

No.10 has 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.

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 spokeswoman has said that the costs “have been met by the prime minister personally” and that party funds “are not being used for this”.

Labour has accused Johnson of having “lied” over the funding, and accused senior members of the Government of a possible “cover-up”.

Transport Secretary Grant Shapps, meanwhile, has insisted a review into the controversy by top civil servant Simon Case will answer whether the Tory party gave Johnson a loan, before the PM paid back the costs.

“I just don’t have the answer but the cabinet secretary will and it will be transparently produced in the annual report and the accounts of the Cabinet Office,” Shapps told Times Radio.

The minister declined to say whether he would have approved the funding when he was party chairman, however, telling BBC Breakfast: “My side of things was the campaigning side of things, I didn’t get involved with the fundraising side of things.”

Johnson was preparing on Wednesday morning to face Labour leader Keir Starmer at prime minister’s questions in the Commons. 

It is likely the PM will be grilled over a number of other allegations which have emerged in recent days.

Johnson is reported to have said he was prepared to let “bodies pile high” rather than order a third shutdown. 

The PM branded the accusation “total rubbish”, but after the Daily Mail first reported the remarks, the BBC and ITV were among those to carry reports with their own sources confirming he made the comment in October.

Downing Street officials have been less firm on a Times report that Johnson separately told aides in September he would rather let coronavirus “rip” than impose a second lockdown.

Johnson’s official spokesman said the reports “distort the actions”  of the PM, but the defence did not amount to a denial.

The bombardment of allegations around the prime minister come as he is embroiled in a public row with Cummings, who until last year was his senior adviser in No.10.

Cummings hit out at his former boss in a blog post, saying he had fallen “below the standards of competence and integrity the country deserves” after No.10 sources – reportedly the prime minister himself – accused him of being behind a series of leaks.

Shadow health secretary Jonathan Ashworth called for a “full and frank” explanation from the PM over the funding of the renovations.

“We really need to know who’s given the loan, who’s given the money, because we need to know who the prime minister, who Boris Johnson, is beholden to,” the Labour MP has told BBC Breakfast. To be honest, he lied yesterday – that’s not good enough.”

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