Workers at the Richards Bay Coal Terminal (RBCT) in South Africa rejected its latest wage offer and will continue to strike, according to the main labour union at the port.

Members of the Association of Mineworkers and Construction Union lowered their demand to a one-year 7% basic salary increase and a housing allowance, said Bheki Sithole, the union’s regional secretary. RBCT, the biggest coal export facility on the continent, offered a minimum 6% annual increase for three years.

Volumes shipped at RBCT have dropped to the lowest level in decades because State-owned ports and rail operator Transnet’s operations have been hobbled by sabotage, cable theft and aging equipment. The walkout by RBCT workers that began September 17 isn’t affecting operations, Sithole said.

RBCT didn’t comment.

Glencore, Thungela Resources and Exxaro Resources are among companies that use the terminal to ship coal.