Several hundred workers at Oman's state oil firm Petroleum Development Oman (PDO) held protests on Tuesday at company headquarters and two oil and gas fields, demanding higher wages.
Around 300 protesting workers in Muscat held up placards outside PDO headquarters. Workers said they also staged stoppages lasting several hours at the Marmul oil field and the Karn Al Alam gas field.
It was not clear if the actions affected production but there are only several hundred workers in each location.
"We are the least-paid oil workers in the Gulf. We want to be paid the same as other oil workers in other gulf countries," said Suleiman Al-Harthy, a PDO staff member.
The workers said they intend to strike again on Wednesday.
The country produces around 800,000 barrels a day of oil, making up over 70 per cent of Oman's income. Oman is the only major Gulf crude exporter that is not a member of producer group OPEC.
PDO produces over 80 per cent of the Gulf Arab state's crude oil and natural gas. The government owns 60 percent of the company and Shell owns around 30 per cent. Total and Portugal's Partex have smaller shares.
The worker strike at PDO is the first one at a national oil company in the Gulf countries since a wave of unrest began sweeping through the Arab world, toppling heads of state in Tunisia and Egypt so far.
The Marmul area contains 12 of around 400 oil fields in Oman, while Karn Al Alam is the country's biggest gas field.
Protesters are pressing political and labour demands across Oman, where a string of concessions from veteran ruler Sultan Qaboos bin Said have failed to bring unrest to an end.
Staff are protesting daily outside other firms including Oman International Bank, Oman Investment Finance Company and Muscat's government-owned Intercontinental hotel, where some guests have been turned away.
Activists have camped out nightly in tents in front of parliament in Muscat, outside the governor's office in Salalah in the far south and in Sohar. They are demanding better wages, more jobs, an elected parliament and a new constitution.