Striking customs workers in Kuwait are not affecting oil exports, the country's oil minister said on Wednesday, the day after employees started industrial action at the country's ports, airport and borders.

Kuwait's customs workers last went on strike in October, in a two-day walkout which disrupted oil shipments from the Opec member state. It was not immediately clear how many were taking part this time, but last year around 3,000 were involved.

Asked whether the strike over wages was affecting shipments, Oil Minister Hani Hussein told reporters: 'No, and in any case we have a backup plan in place and our government is talking with the strikers to resolve things.'    

The country produces around 3 million barrels of oil a day, according to the state oil company KPC.     

Last year's strike halted vessel traffic in and out of Kuwaiti ports, including at least five oil tankers. 

On Monday Kuwait's government, under pressure from labour unions, announced a 25 percent pay increase for state workers but representatives from several sectors have said the increase is not enough.

The upward pressure on wages in Kuwait, partly due to increased union activity since last year's Arab Spring social unrest in the region, has become a major issue for economic policymakers. The finance minister said last year that public sector wages had risen to about 85 percent of the country's oil revenues, which he called 'a real danger'. 

Last month Kuwait's central bank governor Sheikh Salem Abdul-Aziz al-Sabah resigned after 25 years in the post, complaining about the rapid rise in government spending. - Reuters