Oil and gas workers have voted in favour of a series of large-scale North Sea strikes amid bumper profits for fossil fuel firms.

About 1,400 workers across five rig-servicing companies plan to strike between late March and early June as part of a dispute over jobs, pay and conditions – potentially shutting down platforms in the region.

The action, coordinated by the Unite union, will involve offshore workers from the contractors Bilfinger UK, Stork, Petrofac, Wood and Sparrows Group.

The contractors work for oil and gas operators including BP, EnQuest, Harbour Energy, Shell and Total. Analysis by Global Witness showed the rigs’ owners made a combined £146bn in profit in 2022.

North Sea oil and gas operators have landed billions of pounds in profits as commodity prices soared after Russia’s invasion of Ukraine. Their booming profits have fuelled calls for better pay for employees and a tougher windfall tax on oil and gas firms.

The Unite general secretary, Sharon Graham, said: “Oil and gas companies have been given free rein to enjoy massive windfall profits in the North Sea; drilling concessions are effectively licences to print money.”

She accused the companies of “raking it but refusing to give [workers] a fair share of the pie”, leading to “a tsunami of industrial unrest in the offshore sector”. “Unite will support these members every step of the way in their fight for better jobs, pay and conditions,” she said.

Greenpeace UK’s head of climate, Mel Evans, said: “The greed is almost palpable. Oil and gas workers have been hung out to dry, while their bosses and shareholders have raked in tens of billions of pounds over the past year.

“It’s no wonder they’re taking industrial action to demand a proper windfall tax on these obscene profits, and we stand in solidarity with them.”

The prospective action includes electrical, production and mechanical technicians as well as deck crew, pipefitters and crane operators.

Workers for Bilfinger, Stork, Petrofac, Wood and Sparrows Group have already voted in favour of strike action. Two further ballots – for 80 Petrofac crew working on BP rigs, and 50 Worley Services staff working for Harbour Energy – could take the number of offshore strikers to more than 1,500 this week.

About 40 Sparrows Group employees on BP rigs accepted a pay offer over the weekend, while about 160 of the firm’s staff on rigs for other companies still plan to strike.

“We are working with our clients to deliver our normal operational services during these periods of action, while ensuring the ongoing safety of personnel and operations,” a Sparrows Group spokesperson said.

Wood said it was “committed to ongoing dialogue” with its employees. “Personnel and operational safety remain our top priority and operations are unaffected at this time,” a spokesperson said.

A spokesperson for Bilfinger UK said: “We engage with unions on all employment matters and are continuing to work with them, our clients and our employees to find a resolution.”

Petrofac has been contacted for comment. Stork could not be reached.

Oil and gas workers have voted in favour of a series of large-scale North Sea strikes amid bumper profits for fossil fuel firms.

About 1,400 workers across five rig-servicing companies plan to strike between late March and early June as part of a dispute over jobs, pay and conditions – potentially shutting down platforms in the region.

The action, coordinated by the Unite union, will involve offshore workers from the contractors Bilfinger UK, Stork, Petrofac, Wood and Sparrows Group.

The contractors work for oil and gas operators including BP, EnQuest, Harbour Energy, Shell and Total. Analysis by Global Witness showed the rigs’ owners made a combined £146bn in profit in 2022.

North Sea oil and gas operators have landed billions of pounds in profits as commodity prices soared after Russia’s invasion of Ukraine. Their booming profits have fuelled calls for better pay for employees and a tougher windfall tax on oil and gas firms.

The Unite general secretary, Sharon Graham, said: “Oil and gas companies have been given free rein to enjoy massive windfall profits in the North Sea; drilling concessions are effectively licences to print money.”

She accused the companies of “raking it but refusing to give [workers] a fair share of the pie”, leading to “a tsunami of industrial unrest in the offshore sector”. “Unite will support these members every step of the way in their fight for better jobs, pay and conditions,” she said.

Greenpeace UK’s head of climate, Mel Evans, said: “The greed is almost palpable. Oil and gas workers have been hung out to dry, while their bosses and shareholders have raked in tens of billions of pounds over the past year.

“It’s no wonder they’re taking industrial action to demand a proper windfall tax on these obscene profits, and we stand in solidarity with them.”

The prospective action includes electrical, production and mechanical technicians as well as deck crew, pipefitters and crane operators.

Workers for Bilfinger, Stork, Petrofac, Wood and Sparrows Group have already voted in favour of strike action. Two further ballots – for 80 Petrofac crew working on BP rigs, and 50 Worley Services staff working for Harbour Energy – could take the number of offshore strikers to more than 1,500 this week.

About 40 Sparrows Group employees on BP rigs accepted a pay offer over the weekend, while about 160 of the firm’s staff on rigs for other companies still plan to strike.

“We are working with our clients to deliver our normal operational services during these periods of action, while ensuring the ongoing safety of personnel and operations,” a Sparrows Group spokesperson said.

Wood said it was “committed to ongoing dialogue” with its employees. “Personnel and operational safety remain our top priority and operations are unaffected at this time,” a spokesperson said.

A spokesperson for Bilfinger UK said: “We engage with unions on all employment matters and are continuing to work with them, our clients and our employees to find a resolution.”

Petrofac has been contacted for comment. Stork could not be reached.