The son of a top aide to London Mayor Boris Johnson has died in Thailand, sources have said.
Andrew Lister, son of deputy mayor and chief of staff Sir Edward Lister, was believed to have fallen ill in the room of his guesthouse on the holiday island of Koh Phangan.
He had reportedly been drinking with friends.
A spokesman for the Foreign Office said: "We can confirm the death of a British national in Koh Phangan, Thailand, on 12 September. We are in touch with the family and helping them at this difficult time."
The Mail on Sunday quoted a Thai police spokesman as saying: "Witnesses said Andrew John Lister was drinking with four friends in room 315 on the Baan Talay Guesthouse on Haad Rin Beach when he collapsed.
"Attempts were made to revive him but they failed. His body was taken to the local hospital.
"We believe he died of a heart attack. There was no evidence of drugs in the room."