Trade body Offshore Energies UK wants an urgent meeting with Chancellor Jeremy Hunt ahead of this month's Budget.
This follows reports at the weekend that the UK Government is preparing to unleash a second round of windfall taxes on North Sea oil and gas producers as part of its cash-raising plans.
It is understood that the levy on offshore operators producers could be raised from 25% to 30% and extended by three years to 2028. Officials have also been working on plans to widen the windfall tax to include electricity generators.
OEUK chief executive Deirdre Michie said last night that "ongoing uncertainty and continuous changes to the fiscal regime are driving investment out of the UK and also encouraging some companies to exit the basin".
She added: "Companies are unable to plan future long-term investments under such uncertain conditions and shareholders, particularly in overseas-headquartered companies, see an increasing risk premium regarding the future of their operations in the UK.
"There is clear evidence that fiscal stability drives investment into the North Sea, and fiscal uncertainty drives investment away from it."
Investment allowance
OEUK also urged the government to protect provisions for an investment allowance for North Sea oil and gas producers, arguing it was "fundamental" for managing risk and supporting further investment in a mature basin.
Ms Michie added: "It is even more needed as tax rates rise - and any changes could further undermine investor confidence. Additionally, any further tax changes being considered should be forward-looking, and any amendments to the measure should not be applied retrospectively."
It emerged yesterday that all Britons are facing years of tax hikes in a bid to balance the country's books,
UK Prime Minister Rishi Sunak and the chancellor are reported to have decided to bring in "stealth" increases in Income Tax and National Insurance over the coming years by freezing the thresholds at which people start to pay different rates.
The pair have agreed that tough decisions would be needed on tax rises, given the "eye-watering size" of the fiscal black hole.
The two leading Tory politicians are said to be eyeing a mixture of tax rises and spending cuts to raise more than £50billion.
Plugging gap
This cash will be used to plug a £40billion gap in the Office for Budget Responsibility forecasts plus create at least £10billion of fiscal headroom to allow for a potential downturn in economic growth.
Former Bank of England Deputy Governor Charlie Bean yesterday said that the government should raid the banks for tens of billions of pounds to help fill the gap in public finances.
The combination of a rising interest rate and the money printed as part of quantitative easing has handed banks windfall profits, he told the Resolution Foundation think tank.
North Sea oil and gas producers are puzzled as to why the government is continuing to target the sector with ever-higher cash demands while the country's banking sector continues to escape scot-free.
The Budget is to be unveiled on November 17, and it will set out tax and spending decisions for the next five years.