Workers at the Indonesian unit of Freeport McMoRan Copper & Gold Inc expect to reach an agreement over pay in less than two weeks, a union official said on Friday, cutting the risk of further disruption at the world's second-biggest copper mine after a deadly accident two months ago.

Freeport halted operations at the copper and gold mine in remote West Papua on May 15, a day after a training area in a tunnel caved in, killing 28 people.

Although the mine has since resumed operations, planned pay talks that began on May 13 were suspended on May 16, before being resumed in late June.

"We expect there will be a pay agreement between the union and Freeport Indonesia management before August so that the Muslim workers will have certainty for their pay before Eid al- Fitr," Papua-based union official Virgo Solossa told Reuters by telephone.

Freeport Indonesia could not be reached for immediate comment.

Relations between Freeport and the union have been strained in recent years following a three-month strike in late 2011 as well as a series of minor spats.

In June, trade union workers called off a planned strike after last-minute talks brokered a deal when they sent a letter to the Freeport management demanding five senior Indonesian employees be suspended after May's accident.

Freeport employs about 24,000 workers, of which three-quarters belong to the union. The 2011 pay deal is due to end on Sept. 30, and talks had been expected to last up to 60 days.

"We hope that the pay talks can be wrapped up as soon as possible and within the first 30 days period and we don't need to prolong it to another 30 days," Solossa added.

Up for discussion are workers' wages, benefits, rights, obligations and pensions, although the exact pay demand is unknown.