Jeremy Hunt is facing a major Tory rebellion over his plan to extend the windfall tax on the profits of oil and gas firms.
The chancellor will announce the move in today’s Budget as he tries to raise cash to pay for a cut in a national insurance.
It will see the so-called “energy profit levy” extended by an extra year until 2029.
But the move is bitterly opposed by Scottish Tory MPs, who say it will put jobs in the north east of Scotland at risk.
In order to implement the change, a new piece of legislation will have to be introduced to parliament.
But Scottish Tory leader Douglas Ross - who confronted Hunt and Rishi Sunak at a reception on Monday night - said he will not vote for it.
He said: “The Scottish Conservatives have a clear position. We will always stand up for the livelihoods of the almost 100,000 Scottish workers who depend on our oil and gas industry.
“Unlike Labour and the SNP who would stop any new developments, we will not support any action that would put those jobs at risk.
“As such, while I support many of the Budget measures, as Scottish Conservative Leader I will not vote for this extension when it is brought before Parliament.
“My Scottish Conservative colleagues and I will continue to have robust discussions with the Chancellor on this matter.”
Nuclear and renewables minister Andrew Bowie, who is MP for West Aberdeenshire and Kincardine, is said to be “on resignation watch” over the policy.
One senior Tory source told HuffPost UK: “Andrew is in a really difficult position on this because it’s right on his doorstep. They’ve put him in an impossible situation.”
The windfall tax was first introduced in May 2022 after a spike in energy prices following Russia’s invasion of Ukraine.
Hunt increased the tax in November 2022 from 25% rate to 35%, and also extended it until 2028 while expanding it to electricity generators with a levy of 45%