A North Sea oil workers strike at the Texas oil company Apache could begin later this month and severely disrupt UK fuel supplies, the Unite union has warned after pay talks collapsed. Unite says action by more than 160 offshore workers could take down the Forties pipeline system, which handles almost a third of the UK's oil and gas.

Which fields and pipelines are at risk

Unite says the stoppage could involve more than 160 Apache offshore workers, among them electrical experts, production technicians and radio operators. Any action would affect the Forties and Beryl oilfields, and Charlie, one of the critical North Sea platforms, could be brought to a standstill.

The union warns that could ultimately take the entire Forties pipeline system down, a system said to handle almost a third of the UK's oil and gas. The disruption could also ripple out and affect other large North Sea operators, Unite said.

Unite industrial officer Stevie Davies said any disruption to Apache's platforms "would have a direct hit on the Forties pipeline and potentially severely affect the UK's fuel supplies". The union blamed the threatened disruption on Apache's failure to reach a pay deal, saying its behaviour could have far-reaching consequences for workers, operators and consumers.

The Apache pay dispute

Unite said Apache offshore staff had emphatically backed strike action over a pay offer it called a real-terms pay cut for many employees. Workers were left with no choice, the union said, accusing the company of making huge profits while offering an unacceptable rise. Texas-based APA Corporation, the parent of Apache North Sea Production, reported $1.4bn (£1.1bn) in after-tax profits and $9.2bn in revenues for last year.

Unite also said Apache had set deadlines for reaching an agreement over back pay and indicated payments could be withheld, potentially leaving workers thousands of pounds out of pocket. General secretary Sharon Graham said: "We will not tolerate unacceptable pay offers."

The union pointed to a precedent from this summer: planned strikes by Neo Next offshore workers were called off after a deal Unite said lifted the pay package by more than £4,000, reached days before workers were due to begin a series of strikes from 22 July.

Apache's response

Apache said it had engaged constructively throughout the pay discussions and believes its final offer to the union is fair and recognises the contribution of its offshore workforce. The company said it had offered staff a 4% pay increase, matching the rise given to its non-unionised employees earlier this year. It described the staff concerned as among the UK's highest earners, whose offshore rota averages 153 working days a year.

On operations, Apache said it has contingency plans and does not expect strike action to affect other producers and their ability to operate through the Forties pipeline system. It added that it plans to maintain safe operations throughout any industrial action. Its plans include:

• •keeping experienced personnel on key sites
• •treating any drop in pipeline pressure during industrial action as similar to what occurs during routine maintenance outages

Fuel prices already under pressure

Consumers are already grappling with rising fuel and gas prices because the US-Israel war on Iran has been disrupting crude and refined oil supplies from the Gulf. On Friday it emerged that the average UK diesel price had climbed to a record £2 a litre. G7 leaders announced they would release up to 100m barrels of emergency diesel and crude oil stockpiles after Donald Trump threatened to cut off supplies of US diesel.

Strike action could begin later this month, according to the union. Ineos, which operates the Forties pipeline system, was contacted for comment.