The United States announced sanctions on Deripaska and Rusal on April 6, preventing customers with U.S. exposure from continuing to buy Rusal's metal and sending aluminium prices to their highest in almost seven years amid fears of a supply shortage.

The government source said Deripaska had also asked for state support for car maker GAZ and had applied for loans for Rusal from Promsvyazbank, a lender that has been taken over by the Russian central bank.

Russian authorities have approved the loan for GAZ, but no decision has yet been made on the loan request for Rusal, the government source said.

GAZ was also sanctioned by the United States.

(Reporting by Darya Korsunskaya; Writing by Andrey Ostroukh; Editing by Andrew Osborn)