Claims that Boris Johnson squeezed a journalist’s thigh under a table during a lunch are “deeply concerning”, a former Tory cabinet minister has said.
Writing in the Sunday Times, Charlotte Edwardes said the incident took place in 1999, but Downing Street called the allegation “untrue”.
Justine Greening, now an independent MP, said it raised “a question about character and integrity”.
But Chancellor Sajid Javid said he had “full faith” in the PM.
Following No 10’s denial on Sunday evening, Ms Edwardes tweeted: “If the prime minister doesn’t recollect the incident then clearly I have a better memory than he does.”
In her first column for the Sunday Times – published on the eve of the Conservative conference in Manchester – Ms Edwardes said she was seated on Mr Johnson’s right at the lunch, held at the Spectator magazine’s offices.
Mr Johnson was editor of the magazine at the time.
“More wine is poured; more wine is drunk. Under the table I feel Johnson’s hand on my thigh. He gives it a squeeze,” she wrote.
“His hand is high up my leg and he has enough inner flesh beneath his fingers to make me sit suddenly upright.”
Ms Edwardes said another woman at the lunch later told her he had done the same to her.
Mr Javid refused to comment on the “personal allegations” against the PM when asked on BBC Breakfast, adding: “The prime minister has said that this is completely untrue.
“I have full faith in the prime minister and I don’t doubt that and what he has said for a second.”
However, Ms Greening told BBC Radio 4’s Today programme: “I can’t comment on those accusations, but they are deeply concerning, and in a sense they go to the heart of this question about character and integrity of people in public life and what standards the electorate have a right to expect.”
At a conference fringe event on Sunday lunchtime, Health Secretary Matt Hancock appeared to play down the claims.
He said Mr Johnson “has never lectured other people about their private lives,” adding: “I think that we should concentrate on delivering on what we are in politics for, which in my view is to serve the citizens of this country.”
Later, though, in an interview with Channel 4 News – conducted before No 10 issued its denial – Mr Hancock stressed that he did not intend to make light of Ms Edwardes’ allegations.
“I don’t dismiss it at all. I have seen how what I said has been… how people have responded to what I said, and [to be] totally clear about it, these issues are incredibly important.”
He said he knew Ms Edwardes well and knew her to be “trustworthy”.
Former minister Amber Rudd – who quit the Conservative Party over its handling of Brexit earlier this month – tweeted that she agreed with Mr Hancock’s conclusion.