A Mexican telecoms tycoon has toppled Bill Gates, the Microsoft co-founder, as the world’s richest man after amassing a $67.8 billion (£33.6 billion) fortune.

Sentido Común, a Mexican financial website, has calculated that Carlos Slim Helú, a 67-year-old turnaround specialist, is worth $8.6 billion more than Mr Gates.

The rocketing share price of América Móvil, one of Mr Slim’s telecoms companies, helped to push him into first place, according to Sentido Comun’s founder Eduardo Garcia.

Shares in América Móvil, Latin America’s biggest telecoms company, rose more than 26 per cent in the three months to June 30. Telmex, another of the tycoon’s telecoms companies, rose 11 per cent and Grupo Financiero Inbursa, his bank, jumped by more than 20 per cent. Microsoft stock went up almost 6 per cent.

The businessman overtook Warren Buffett, the legendary investor, as the world’s second-richest man in April, according to Forbes magazine.

It is the second time that Mr Gates has been reported to have lost his crown. Three years ago Veckans Affärer, a Swedish magazine, said that Ingvar Kamprad, the Ikea founder, had become the world’s richest man.

Unlike Mr Gates, who stepped away from the day-to-day running of Microsoft in 2000, Mr Slim remains actively involved in his companies. His sons, Carlos Slim Domit, Marco Antonio Slim Domit and Patrick Slim Domit, run businesses within the group.

Telmex operates 90 per cent of the telephone lines in Mexico. Another Slim business, Telcel, supplies almost 80 per cent of the country’s mobile phones. Mr Slim acquired Telmex for $1.8 billion in 1990.

Mr Slim also owns Grupo Carso, an industrial company, with interests in shops and restaurants, most of which he bought during the economic crisis that hit Latin America in the 1980s.

The son of a Lebanese immigrant shopkeeper, Mr Slim was widowed in 1999. The name Carso comes from the first three letters of his name and the first two of his late wife, Soumaya Gemayel.

Times Recommends

• Lies and cover-up at MG Rover exposed by report
• High oil prices push manufacturing costs up
• Primark founder steps down as chief executive