The UK Government is today reported to be drawing up plans to expand the recently-introduced windfall tax to raise billions of pounds more to help balance the country's books.
Proposals are thought to include increasing the levy on North Sea oil and gas producers, as well as extending its lifespan.
Renewable energy generators such as wind farms could also be targeted in a new round of the windfall tax - replacing the price cap on the sector introduced by Jacob Rees-Mogg, the former business secretary, earlier this month.
Nadhim Zahawi, the Tory chairman, has suggested that the windfall tax could be extended in next month's budget.
The Telegraph reports that Ben van Beurden, the chief executive of Shell, conceded yesterday that there was a case for such a levy, but said that producers should be "at the table" to make sure any new taxes were designed in a "correct and appropriate" way.
Asked if Shell was actively engaging with the Treasury about the design of any additional UK taxes, Mr van Beurden said: "We have spoken with the Government many times in the lead up to the levy put in place by the then-chancellor earlier in the year.
Continuous dialogue
"I am absolutely certain that we are indeed in continuous dialogue with the Treasury on these matters, in a constructive way.
"But not me personally, at this point in time. I would imagine that moment may still come. But of course, I'm also very mindful that it's a very busy time at this stage for the Government."
When asked about a possible expansion of the windfall tax, a spokesman for the Prime Minister said: "No options are off the table given the economic circumstances."
Separately, it is understood that the Treasury is also looking at increasing the tax that banks have to pay on the profits they make.
Mr Zahawi has also suggested that the state pension triple lock will be kept in place after No 10 refused to commit to the pledge.
He said: "Pensioners are uniquely - and I'm going to state the bleeding obvious here - they're unique in that they can't take on work to increase their income and therefore are uniquely vulnerable.
"And I know that the Prime Minister and the Chancellor will be very, very conscious of that fact."