In a move that surprises absolutely no one who has watched a government wrestle with its own manifesto, the Jackdaw gasfield will be given the go-ahead on Wednesday. The announcement, to be made from Aberdeen by energy secretary Miatta Fahnbulleh and chancellor John Healey, signals a commitment to the North Sea fossil fuel industry that threatens to trigger a row with climate campaigners and Labour MPs. It only took over a year of deliberations to decide whether approving drilling at one of the biggest undeveloped fields in the declining North Sea basin would violate the UK's climate commitments. Spoiler: they've decided it won't.

The approval is a big boost for Britain's oil and gas industry - and especially for Shell and the Norwegian company Equinor, which operate the field. Climate campaigners, meanwhile, are expected to be outraged, arguing it undermines Labour's green credentials and will exacerbate the climate crisis. Tessa Khan, executive director of the anti-oil campaign group Uplift, noted: "Jackdaw will provide around just 2% of our gas demand for roughly 10 years. It has been oversold and won't stop the overall decline in North Sea jobs, as it will be largely unmanned and operated remotely." She added, with admirable understatement: "Labour's climate credibility is on the line. No new oil and gasfields are compatible with safe climate limits."

When fully operational, Jackdaw will account for 6% of North Sea gas production, making it one of the biggest gasfields not yet under production. Along with the Rosebank oilfield, its status had become totemic of the government's commitment to the oil and gas industry, which is facing heavy job losses as reserves decline and platforms become increasingly automated. The field was originally approved by the Conservative government in 2022, with ministers arguing it would help shield the UK from energy market volatility caused by Russia's invasion of Ukraine. Labour came to power in 2024 on a promise not to grant any new licences in the North Sea, not expecting they would have to make a decision on either Jackdaw or Rosebank. Ah, the optimism of opposition.

However, both fields were cast into doubt last year by a landmark ruling that said their environmental approval had been incorrectly granted. A judge ruled that regulators should have taken into account the carbon emissions generated by burning the oil and gas the two fields will produce when deciding whether they would violate the UK's climate commitments. Shell and Equinor resubmitted their application for environmental consent last September. Since then, Fahnbulleh and her predecessor, Ed Miliband, have spent months deciding whether to use their ministerial power to block it. Both the prime minister and his predecessor, Keir Starmer, have come under heavy pressure to allow the fields to go ahead in recent months, not least from US president Donald Trump, who urged both men to "open up the North Sea". Because nothing says energy independence like taking advice from a man who once suggested injecting bleach.

Burnham signalled he was sympathetic to the president's arguments earlier this summer, promising to take a "pragmatic approach" to the decision. "There is a resource there," he added in July. "When people are struggling - you can't ignore that." He told the Commons last week: "I will take a pragmatic approach on oil and gas, we will set out our decisions shortly." And by "shortly", he apparently meant "Wednesday".

Multiple sources have told the Guardian that Fahnbulleh has now decided not to block the field, allowing the North Sea Transition Authority (NSTA), which regulates the industry, to give the go-ahead based on financial and logistical concerns. She will make the announcement alongside Healey and the NSTA's chief executive, Stuart Payne, on Wednesday. They will say that granting the environmental approval does not violate Labour's manifesto commitment because it is not a new licence. A distinction that will surely comfort the glaciers.

Fahnbulleh is understood not to have made a final decision on the larger Rosebank field, but energy department officials are looking at ways the tax proceeds from the project could go to green projects if it was given. A decision is expected later in the year. The Jackdaw announcement could boost Labour's position in the north-east of Scotland, where much of the industry is based and where unions have been campaigning heavily for the permits to be granted. But it is likely to cause angst among some Labour MPs, especially those in seats where they face a challenge from the Green party.

A poll by Savanta for the climate group E3G and seen by the Guardian shows that nearly a third of voters say they would be less likely to vote Labour if it gives the go-ahead for more North Sea oil drilling. That includes almost exactly a third of those who voted Labour at the last election, and around half of 18-24-year-olds. Ellie Mae O'Hagan, UK energy programme lead at E3G, said: "After a summer of deadly heatwaves, the public has made up its mind: more drilling is the wrong answer. If the prime minister wants a decade in power to change the country, he should invest in heat pumps and solar, not tax breaks for the oil and gas companies driving up our bills and polluting the planet."

Officials say, however, that the Rosebank decision is likely to be the more sensitive one, partly because it will produce around seven times the CO2 emissions and partly because most of the oil produced there will be exported. Khan said: "The defining test is Rosebank. Burnham must deliver on his promise and prioritise affordable bills, genuine industrial growth and a safe climate over oil profits. That means rejecting Rosebank." So, no pressure.