Tintin, the eternal boy reporter, marks his 80th birthday today but, for France, the celebrations have been soured by a perfidious claim from across the Channel that the comic strip hero is gay.

An article by Matthew Parris, The Times columnist, on Tintin’s “obvious” homosexuality has triggered an outcry in the media and on the internet.

“They have walked on Tintin,” said the headline in French newspaper le Figaro, attacking The Times for “reviving for the upteenth time” the sexual orientation of Europe’s most venerated comic strip hero. The headline was a play on They have walked on the Moon, one of Tintin’s greatest adventures.

France has long adored Tintin as one of its own although his creator, Georges Remy, known as Hergé, was a French-speaking Belgian. That explains the patriotic reflex over Parris’s recital of the long-standing belief among gays that Tintin is one of their own.

“What debate can there be when the evidence is so overwhelmingly one-way?” Parris asked. “A callow, androgynous, blonde-quiffed youth in funny trousers and a scarf moving into the country mansion of his best friend, a middle-aged sailor? A sweet-faced lad devoted to a fluffy white toy terrier, whose other closest pals are an inseparable couple of detectives in bowler hats.”

The theory may have been around since it became the subject of books in the 1970s, but it was too much for some French critics coming from un anglais on the anniversary of Tintin’s appearance in a Brussels children’s newspaper.

“At this age the hormones are usually asleep,” sniffed Les Echos, the main business daily. “But for Matthew Parris, it is never too late to wake up the houppette of the nice Belgian hero.” Houppette means both quiff and powder puff. What next, wondered les Echos? Asterix and Obelix as lovers? “That’s perhaps the next subject for a column by Matthew Parris.”

Le Figaro even hauled in Serge Tisseron, a celebrity psychiatrist, to explain that claiming the hero as gay “is a lovely revenge for a homosexual”.

“The problem is that the sexual dimension is totally absent. Tintin is a creature whose sex is never defined. Beware of launching into a sexual reading of Hergé’s works. In reality all the characters in Tintin are children.”

Le Figaro’s article produced a torrent of mainly conservative internet comments pointing out that Hergé was drawing and writing at a time when boys’s adventure stories were allowed to be violent (as Tintin was) but steered well clear of romance or sex.

France Info, the public news radio network, got in on the subject, pointing out that Hergé, who died in 1983, scoffed at the gay Tintin theory after it was aired in the 1970s.

The standard view among Tintin fans is that the gay argument is irrelevant.

Hervé Gattegno, Tintinophile and well-known investigative journalist, said recently that it did not matter whether his hero might be gay or not. Born in the Catholic prewar culture, sex and love were kept out of the stories. “The values which are defended in the Tintin adventures are those of comradeship, friendship, solidarity and fraternity.”

Tintin is, however, no stranger to controversy in Britain. In 2007 the Commission for Racial Equality urged the withdrawal of Tintin in the Congo from sale alleging it was racist.

Tintin’s fame is soon to extend beyond his European home to the United States – where he has never been popular. Steven Spielberg is producing a long-awaited Hollywood version for release next year.

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