A man, believed to be from Bath, is being held in Thailand on suspicion of drugs offences.
Benjamin Cox, 22, was arrested in Pattaya on 22 December and is in prison awaiting trial.
He was allegedly caught with 2.25g of crystal methamphetamine and drug-taking paraphernalia.
A Foreign and Commonwealth Office spokesman confirmed Mr Cox's arrest and said: "We have provided consular assistance."
Drugs offences carry severe penalties in Thailand, including the death penalty.