The Russian government has fired Sergei Vybornov as head of Alrosa, the world’s second biggest diamond producer, amid allegations by Russia’s budget watchdog that the company had blocked access to its accounts under his watch.

Mr Vybornov, who led since 2007 the state-controlled company that produces 25 per cent of the world’s diamonds, is to be replaced by Fyodor Andreyev, deputy head of Russian Railways – another big Russian state monopoly controlled by Vladimir Yakunin, an influential ally of Vladimir Putin.