Nicola Sturgeon has called on Boris Johnson to “reassess” the licence for an oil field near Shetland given the “severity of the climate emergency we now face”.

Opponents of plans for fossil fuel extraction from the Cambo oil field say it risks sending mixed messages ahead of the UK hosting the COP26 climate summit in Glasgow later this year.

Calls to oppose the development gained further traction this week with the release of a report from the UN’s Intergovernmental Panel on Climate Change.

This warned that heatwaves, flooding and droughts will be more frequent and more intense as the world is set to hit the 1.5C global warming limit within the next 20 years.

It is estimated the Cambo oil field will produce 132 million tonnes of carbon during its lifetime.

It is estimated to contain 800 million barrels of oil and is co-owned by Shell and the private equity backed Siccar Point Energy.

The licence to develop the field was awarded in 2001, but UK government regulator The Oil and Gas Authority is due to give it final approval to go into production.

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In her letter to the PM, Ms Sturgeon said licences such as the one for Cambo “should be reassessed in light of the severity of the climate emergency we now face, and against a compatibility checkpoint that is fully aligned with our climate change targets and obligations”.

“We are both well aware of the importance of oil and gas over many decades – not least in terms of jobs – to the Scottish and UK economies,” the first minister said.

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‘We can’t just tear up contracts’ – PM on oil field plan

“We also understand that reducing reliance on domestic production of oil and gas, which we must do, without increasing imports – which would potentially increase emissions – depends on the development of alternatives.

“However, the answer to these challenges – given the urgency of the climate emergency – cannot be business as usual.

“Instead, we must take decisions and make investments now to support – and accelerate -the development of these alternatives and thereby secure a just, but appropriately rapid, transition for the oil and gas industry, and the workers and communities currently reliant on it.”

The first minister said the “knowledge and experience” of the oil and gas sector, along with its supply chain, should be utilised to create more renewable opportunities.

Ms Sturgeon also called for a summit involving the four nations of the UK to be held ahead of COP26 and for the UK government officials to “provide clear leadership” ahead of those talks.

Questioned about Cambo during a visit to Scotland last week, Mr Johnson said contracts that have already been agreed for work in the North Sea “should not just be ripped up”.

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Climate Report: Code red for humanity

But the PM said there was a need to “transition as fast as we reasonably can” away from oil and gas.

Reacting to the first minister’s letter, Greenpeace UK dismissed it as a “PR exercise”.

Campaigner Sam Chetan-Walsh said: “Nicola Sturgeon is deferring to Boris Johnson to check the climate impact of Cambo, but until she makes her own stance clear this is just a PR exercise.

“The experts couldn’t be clearer – humanity is at code red, and the last thing we can afford is a new oilfield which would pump out the equivalent emissions of 18 coal-fired power stations running for a year.

“The first minister must stop hiding behind Boris Johnson. If she wants to show leadership on climate she must clearly say, ‘Stop Cambo’.”

Scottish Labour’s net-zero spokeswoman Monica Lennon said the first minister should “get off the fence and oppose the Cambo oil field plans in the face of climate catastrophe”.

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She added: “In the wake of growing pressure from grassroots campaigners, she has taken a baby step towards having a position. Now is not the time to reassess.

“It’s time for Nicola Sturgeon to firmly and loudly oppose Cambo, once and for all.”

Mark Russell, environment spokesman for the Scottish Greens, said: “It is welcome to see the Scottish government start to come off the fence when it comes to the Cambo oil field, but it is clear there are still far too many hopes pinned on the oil and gas industry to get us out of the climate emergency.”

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