Mikhail Prokhorov offered yesterday to sell his blocking stake in Norilsk Nickel for $15.7bn to his former partner Vladimir Potanin, in what he said was a gesture of "goodwill" aimed at resolving a standoff over the carve-up of their assets.

But the deadlock over dividing the Russian billionaires' holdings in the world's largest nickel miner looked set to continue, after Mr Potanin's company, Interros, indicated it would be impossible to meet Mr Prokhorov's condition that payment be completed within 45 days.