Rio Tinto Group, the world's third-largest mining company, is in talks to raise cash from Aluminum Corp of China, tapping its largest shareholder to reduce $38.9 billion of debt.

Aluminum Corp, known as Chinalco, may buy convertible debt in Rio Tinto and or minority stakes in some of its units, the London-based company said yesterday in a statement. The sales may raise as much as $15 billion, UK's Sunday Telegraph reported on Sunday. Rio's shares closed 5.5 percent higher in Sydney.

Rio's Chief Executive Officer Tom Albanese, who rejected a takeover offer from BHP Billiton Ltd, is studying a share sale after commodity prices plunged the most in more than 50 years in 2008 and the company's debt ballooned 19-fold with the purchase of Alcan Inc.