North Sea workers are to stage a 48-hour strike next week in a dispute over their pay and allowances.
The action will affect seven Shell platforms from 6:30am on 4 August.
Members of the Unite and RMT unions are in dispute with their employer Wood Group.
The action follows industrial action this week, including a 24-hour stoppage on Tuesday.
Next week’s strike affects the Shearwater, Gannet, Nelson, Curlew, Brent Alpha, Brent Bravo and Brent Charlie platforms.
Union officials say workers’ pay and allowances could be cut by as much as 30 per cent following the downturn in the industry.
Dave Stewart, chief executive officer for Wood Group’s eastern region business unit, said: “We are hugely disappointed that the significant movements we have made to reach a resolution have clearly not been acknowledged by the unions.
“I must stress none of our employees are being offered terms and conditions below the Offshore Partnership Agreement, agreed by the unions only this year; nor will they be.
“The majority of our employees will still be paid significantly above these terms and conditions.
“Safeguarding these jobs in the North Sea now and in the future against the backdrop of an extremely challenging economic climate remains our firm commitment.
“It is estimated that 120,000 jobs will be lost in the UK by the end of 2016 due to the prolonged low oil price.
“We believe safeguarding jobs should be a mutual goal shared by the unions and we would encourage them to work with us to realign the cost base if we are to sustain this mature industry and employment opportunities long into the future.”
Offshore trade unions, Unite and RMT have called on Wood Group to drop its cuts to pay and allowances and hold further talks to resolve the dispute.
Unite Regional Officer John Boland, said: “Wood Group needs to move away from constantly attacking the terms and conditions of its workforce and move on to a more positive agenda of working with the unions to overcome the problems affecting the offshore oil industry.
“Wood Group needs to drop the cuts and get back round the table with us if it genuinely wants to avoid further industrial action.”