An immigration official told a local newspaper that when the man was asked about a tattoo of Buddha on his arm he had spoken “very disrespectfully”.
Such views would have been a “threat to his own safety” in Sri Lanka, he added.
The authorities are tough on perceived insults to Buddhism – the religion of the island’s majority ethnic Sinhalese.
Last year, three French tourists were given suspended prison sentences for taking photographs that showed them pretending to kiss a statue of Buddha at a temple.
In 2010, the American R&B star Akon was refused a visa after protests over one of his music videos, which featured scantily-clad women dancing in front of a statue of Buddha.
An official at Bandaranaike International Airport told AFP news agency that the report of Friday’s incident involving the British tourist was correct.
More than 100,000 British citizens visited Sri Lanka in 2012, accounting for 10% of the total number of tourists. The UK is also the country’s second-largest trading partner after India.
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