Sir Keir Starmer met Taylor Swift when he attended her concert in Wembley, 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.
It had not been clear previously if the two had met.
Sir Keir’s attendance at the concert has been the focus of increased scrutiny in recent weeks after Swift was given an enhanced police escort.
It is understood there was no discussion about the provision of security for the artist, which Downing Street said was an independent operational matter for the police.
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.
It 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 dance class.
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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