Freeport-McMoRan Copper & Gold is loading two ships at its Indonesian port, sources said on Thursday, in a fresh sign that work at the world's second largest copper mine is returning to normal after a three-month strike.

The two ships, with a capacity of 66,000 tonnes, were destined for India and Japan, but their contents and exact volume were unknown, said the sources, who declined to be identified.

Arizona-based Freeport has had a force majeure in place since last October on some concentrate exports from its huge Grasberg copper and gold mine in Papua, after workers went on strike for better pay.

The strike ended on Dec. 14 with a deal over a pay increase, allowing workers to gradually return to work, but the force majeure has yet to be officially lifted.

Last week, Indonesia's PT Smelting and Japan's Pan Pacific Copper said they had started to receive copper concentrate shipments again from Freeport Indonesia.