His remarks came after reports that Conservative Party funds had met a large part of the bill for the makeover the residence Mr Johnson shares with his fiancée, Carrie Symonds, which is said to be in the region of £200,000.
Last week, the Daily Mail also reported the prime minister planned to set up a charity to fund the costs of the works to the flat above No 11, which has been used as the official residence of prime minister’s for many years.
It was added the scheme could be based on one used by the White House to raise millions of dollars for interior design, antiques and art.
But in his first public comments on the renovations during a No 10 briefing, Mr Johnson refused to answer whether any costs for the flat had been settled by either Conservative HQ or private donors, and whether now was the “right moment” for the expensive makeover.
“All I can say is all such inquiries will be answered with normal declarations in the normal way,” the prime minister replied.
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Earlier, the prime minister’s press secretary Allegra Stratton, however, told reporters during a briefing that Conservative Party funds “are not being used to pay for any refurbishments of the Downing Street estate”.
She said the Conservative HQ “supports the leader of the Tory party in their political activities but not in the way it is being accused of”.
Pressed on whether the party had encouraged private donors to contributed towards the costs of the renovations, Ms Stratton said any donations would be declared through the Electoral Commission, the House of Commons’ register of members’ interests, or in ministerial transparency declarations.
“At every twist and turn of this there will be records and reports,” she said.
Ms Stratton added on Monday that details of the Downing Street works will be included in the Cabinet Office annual report which is due to be published in July.
“It will have the relevant level of information to make it clear what refurbishment and what renovations took place in the last year on Downing Street.”
She would not confirm that donations or gifts had contributed to the refurbishment, but told reporters: “I’m saying that all donations, gifts and benefits will be declared in transparency returns that you - we - will all get and be able to pore over in the fullness of time.”
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