(IDEX Online) - Alrosa and Endiama are reported to be heading for a messy divorce over Catoca, the world's fourth biggest diamond mine.The Russian and Angolan mining companies, both state-controlled hold 41 per cent and 59 per cent stakes respectively in Sociedade Mineira de Catoca, the company that operates the mine.Angola is pushing for Alrosa to withdraw unconditionally from the venture, according to the Portuguese-language newspaper Expansao, because it is now subject to G7 sanctions.But Alrosa, which developed the Catoca's production complex, is said to be demanding compensation for the investment it has made in the mine, which started commercial production in 1997.Both sides are reported to have last week in Dubai to see if they could resolve their problems.Endiama's president Ganga Junior said banks and external suppliers were wary of working with it because of its Russian links.Alrosa's stake in the mine was not enough to trigger US sanctions that were imposed shortly after the invasion of Ukraine almost two years ago.A consortium of Indian investors reportedly expressed an interest in acquiring Alrosa's share.Pic of Catoca mine.