Oil and gas producers on the North Sea could leave 500 million barrels of oil equivalent in the ground over the next decade due to windfall taxes, the equivalent of one year’s production in the ageing basin, according to the industry association OEUK.

In the past year, Britain has implemented windfall taxes on oil and gas and renewables, which the industry claim discourages investment and would likely increase the country’s reliance on imported fuels and derail its climate goals.

Ross Dornan, market intelligence manager at Offshore Energies UK (OEUK), told reporters that the levies are anticipated to limit investment in the oil and gas industry by £3 billion and £5 billion over the next decade.

Despite a tax benefit of approximately 91 pence per pound invested in new hydrocarbon production, which renewables producers also request for their industry, this fall in investment is anticipated.

Last year, the North Sea produced just under 1.4 million barrels of oil per day, down from a 1999 high of over 4.4 million barrels.

“When we discuss investment in the UK’s oil and gas resources, we are not discussing exponential growth, but rather managed decline,” said Dornan. Britain will likely generate 500 million barrels fewer, enough to support the nation for six months.

The British government is expected to announce energy security measures on Thursday, including changes to taxation and investment incentives for the offshore industry.

Any new incentives for oil producers are sure to be criticised by climate activists, especially in light of the weekend oil disaster at the Anglo-French oil company Wytch Farm’s Dorset field.

Harbour, the largest oil and gas producer in the United Kingdom, has announced job layoffs and rejected the most recent licencing cycle. TotalEnergies slashed its United Kingdom investment plan by a fifth.

Development of the world’s largest wind farm off the coast of Britain is in jeopardy; it requires additional financing to move forward with the project.