There are warnings strikes at two liquified natural gas (LNG) plants in Western Australia this week could impact the state's energy supply.
The workers at Chevron's Wheatstone and Gorgon gas facilities voted to continue the industrial action starting on Thursday.
The move came after the giant energy company and trade unions appeared at the Fair Work Commission last week.
The Offshore Alliance, which represents the workers, said on social media that it held a secret ballot of members over the past weekend and 91 per cent from the 410 members who participated backed strike action.
Last month, an in-principle agreement between Chevron and the workers at the two plants was reached following strikes.
But the Offshore Alliance claimed Chevron was backpedalling on some parts of the deal.
Chevron said the move to restart strike action was "very concerning" and it was counter to advice given to the union by the Fair Work Commissioner.
"The union's decision to ignore the recommendation to withdraw the protected industrial action notice while discussions are continuing is very concerning, unreasonable and undermines the considerable progress made prior to Chevron requesting the commission's assistance last week." a Chevron spokesperson said.
"We're continuing work to conclude the drafting of proposed enterprise agreements for our Gorgon and Wheatstone facilities based on the clarifications provided by the Fair Work Commission."
The two Chevron plants in the Pilbara supply about 44 per cent of WA's domestic gas supply and 6.6 per cent of the world's LNG stocks.
Energy market analyst EnergyQuest said the Wheatstone and Gorgon facilities produce an estimated $76 million in daily revenue.
"The Chevron industrial negotiations are not for the faint-hearted. They put at risk a third of Australia's LNG exports and almost half of Western Australia's domestic gas supply," EnergyQuest CEO Rick WIlliamson said.
The two WA projects also export LNG to Japan and China.
"Japan, as Australia's largest buyer of LNG, now has 16 per cent of its national LNG supply caught up in one industrial dispute in Western Australia," Williamson said.
