The co-creator of Astérix, France’s comic strip hero, has betrayed the Gaulish warrior to the modern-day Romans — “the men of industry and finance” — his daughter claimed yesterday.

Sylvie Uderzo, 46, subjected Albert Uderzo, her 81-year-old father, to a public lashing for selling the family publishing firm and the right to produce new Astérix adventures after his death.

“It is as if the gates of the Gaulish village had been thrown open to the Roman Empire,” Ms Uderzo wrote in an appeal to Astérix fans, a group that includes just about the whole of modern Gaul. She added: “I am entering resistance against perhaps the worst enemies of Astérix, the men of finance and industry.” Calling Astérix her brother, Ms Uderzo accused her father’s advisers of pushing him to break a promise to forbid others to produce new tales after his death. Hergé, the late creator of Belgium’s Tintin, left a similar ban in the interest of preserving his heritage, she noted. “They made [Uderzo].. deny the values with which he brought me up: independence, brotherhood, friendship and resistance,” she said in le Monde newspaper.

Mr Uderzo, who invented the plucky Gaul in 1959 with the late René Goscinny, sold control of Albert René, the family-run firm, last month to Hachette, France’s biggest publishing concern. He had already fallen out with his daughter, sacking her in 2007 from her post as managing director of the firm.

As well as artistic integrity, large sums of money are involved. Astérix, the much-loved symbol of French resistance against occupying enemies, brings the firm up to 25 million euros a year from 33 strip albums plus lucrative film and merchandising rights and a popular theme park in the Paris outskirts.

Over 325 million albums have been sold and Mr Uderzo, who continued production after the death of his partner in 1977, is working on a new album for this year’s 50th birthday.

Ms Uderzo, who still holds 40 per cent of the firm, is suing her father and trying to block the Hachette deal. Anne Goscinny, daughter of Astérix’s other creator, said that she regretted Ms Uderzo’s action, which she put down to a father-daughter feud.

“This is about a very painful family story,” she told The Times. “I love Sylvie like my sister... But Astérix is a very strong character. Astérix will guide those who take him in hand and not the other way around,” she said. “I am very confident and I do not worry at all that he will be watered down... I find it sad that Tintin died with Hergé.”

Mr Uderzo, originally the illustrator of Goscinny’s stories, said last month that he had placed Astérix in safe hands so that he could concentrate on writing and illustrating new adventures.

Arnaud Nourry, the chief of Hachette, said at the time: “I promise before Albert Uderzo and Anne Goscinny that Astérix will still be a star in a hundred years time.”

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