Around 80 percent of workers at Kuwait's main, state-run oil services company are on strike calling for better pay, a union official said on Tuesday, the latest sign of wage pressures in the Gulf Arab country.

The walkout by the workers, who provide security, fire protection and health services for oil firms, began on Sunday but had not affected oil production in the Opec member state, union official Saad al-Sebayie said.

Well over 1,000 of around 1,400 staff at Oil Sector Services Co. (OSSC), owned by Kuwait Petroleum Corporation, have been gathering in a union building instead of turning up for work, he said. OSSC was not immediately available for comment.

The workers were asking for their jobs to be moved to a higher pay bracket, Sebayie said. The union had warned state oil companies of the planned action in advance, he added.

Policymakers and economists have warned that steep growth in public sector salaries is unsustainable in the long-term in a country where over 80 percent of nationals work for the state.

After the cabinet agreed a 25 percent pay rise for state employees in March last year, customs workers responded by going on strike for even bigger hikes. They were joined by workers at state-run Kuwait Airways, whose walkout grounded flights.

Strikes are fairly common among public sector workers in Kuwait, one of the world's richest countries per capita, whereas industrial action is rare in other Gulf states like the United Arab Emirares, where unions are banned. – Reuters