The billionaire wife of the Mayor of Moscow is being sued for £120 million by her brother over his sacking from their building company.

Viktor Baturin claims that his younger sister, Elena, failed to tell him that he had been fired from Inteko, a multi-billion pound construction and real estate business.

Ms Baturina, 43, is married to Yuri Luzkhov, Moscow’s powerful 70-year-old mayor, and has grown rich from building projects since he took office in 1992. Her company is said to control 20 per cent of construction in the booming capital, earning the former factory worker an estimated personal fortune of £1.6 billion. She and her brother founded Inteko in 1991 and worked together for almost 15 years until a split in December 2005.

The company announced his departure as vice-president a month later.

Mr Baturin told The Times that he was also sueing his sister for recovery of lost shares in the company, which he said were worth as much as £500 million. He insisted that the legal action was not personal, adding: “How could I be upset at my younger sister? We celebrate the holidays and talk on the telephone to each other.”

However, the feud threatens to turn an uncomfortable spotlight on a notoriously publicity-shy company if the case goes to court. An initial hearing has been set for January 30 at a district court in Moscow.

Reports suggest that the siblings fell out over a land deal involving a subsidiary of Inteko in the Belgorod region, close to Russia’s border with Ukraine. It became embroiled in a bitter dispute over farmland with the regional authorities, which the company says led to the murder of one of its lawyers in October 2005.

Ms Baturina handed full ownership of the subsidiary, Inteko-Agro, to her brother when he left Inteko.

Inteko also announced in March that it had bought out Mr Baturin’s 1 per cent share of the parent company for $21 million (£10.5 million) — Ms Baturina already owned the other 99 per cent. Mr Baturin insisted, however, that he had a 25 per cent stake in Inteko until the shares disappeared from the accounts in 2002 or 2003.”

An Inteko spokeswoman declined to comment. Mr Baturin said that he had been pressing the company for an explanation, and had started legal action now because a 12-month deadline for bringing court cases was approaching.

His lawyer argues that he was dismissed illegally because the company did not inform him formally that he had been fired. He is claiming compensation for loss of salary, untaken holiday and the return of an employment record book detailing his pension payments.

Mr Baturin declared shortly after he left the company that there was “no conflict” between him and Inteko.

Ms Baturina is a formidable opponent. She threatened to sue the Russian edition of Forbes magazine last month after objecting to a frontcover headline for an interview it had conducted with her.

Its German publisher, Axel Springer, prompted protests from journalists by pulping the entire December edition and printing a revised version. The original headline under a photograph of Ms Baturina said “My protection is ensured” in a sly reference to her company’s political connections. The revised cover stated: “Like any investor, my rights are protected.” The article detailed how Ms Baturina had restructured her business away from dependence on construction contracts ahead of her husband’s retirement as Mayor of Moscow later this year.

Ms Baturina is Mr Luzkhov’s second wife. The couple met in 1987 when they served on a Soviet-era municipal commission. The couple have two daughters aged 14 and 12.

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