Sir Keir Starmer met Taylor Swift when he attended her concert at Wembley Stadium, Sky News understands.
It has emerged the prime minister and his family spoke to the pop star and her mum for 10 minutes and discussed the Southport stabbings.
The revelation comes amid questions over government intervention in talks over the security for the concerts after Swift was given a taxpayer-funded police escort despite reservations from the Met.
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It had not been clear previously if Sir Keir and Swift had met at the gig.
There was no discussion about the provision of security for the artist, which Downing Street said was an independent operational matter for police, it is understood.
Sir Keir and his family were given free tickets to the concert on 20 August, which were declared as required, and have since been paid back.
Taylor Swift performing at Wembley Stadium. Pic: AP
The meeting came after the superstar cancelled gigs on her Eras Tour in Austria due to a terror threat, and the mass stabbing in Southport at a Taylor Swift-themed dance class, when three young girls were killed.
Sir Keir was invited to the August show by Universal Music, which is based in his constituency of Holborn and St Pancras.
He paid back the cost of the tickets after a row over ministers accepting freebies dominated headlines during his first 100 days.
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Questions over Taylor Swift motorcade
Further questions were raised after a report in The Sun alleged Home Secretary Yvette Cooper and London Mayor Sadiq Khan spoke to the Metropolitan Police to encourage them to give the megastar a “VVIP escort”, when she returned to the capital to complete the European leg of her sell-out tour in August.
The Met was reportedly reluctant to sign it off as a blue-light escort is typically reserved for senior members of the Royal Family and high-level politicians, because it comes at huge expense to the taxpayer, the newspaper reported.
Swift’s mother Andrea, who is also her manager, apparently threatened to pull her daughter’s three shows if the police convoy was not provided.
The government has denied that senior Labour figures were given tickets to the shows in exchange for police protection, stressing the Met makes decisions independently from politicians.
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Last week, deputy prime minister Angela Rayner said it was down to the fact Swift’s concerts in Vienna had been cancelled due to a foiled terror attack, which was intended to kill tens of thousands of fans.
“We needed to make sure that that person was safe. And it was a policing matter, not an issue for politicians. It was the police that make the decision,” she said.
She added that police provided the security to ensure Swift could continue with the concerts “which brought in huge amounts of investment of money into our economy, including those small businesses that need that support”.
Culture Secretary Lisa Nandy told Sky News “you would expect” the home secretary and the mayor to be involved in a conversation “where there is a security risk”, such as after the Vienna bomb plot.
“I really utterly reject that there’s been any kind of wrongdoing or undue influence in this case,” she said.
