Billionaire Sir Jim Ratcliffe's INEOS made nearly £500million in profits from its oil and gas operation last year.
The Telegraph reports today that INEOS UK E&P Holdings raced into the black in 2021 - making £474million in profits, compared to £226million losses a year earlier.
The firm said this was driven by the major rises in the price of oil and gas, as demand ballooned as Covid restrictions eased.
Ineos UK E&P said oil prices went from around $39 per barrel in 2020 to $72 per barrel last year, while gas prices rose from 25.2p per therm to 91p per therm.
Since then, prices have pushed even higher following Russia's invasion of Ukraine and the ensuing sanctions on the country.
The Telegraph said INEOS did not respond to requests for comment about the results.
INEOS Oil & Gas UK has focus areas West of Shetland and in the southern North Sea.
Gas fields off Shetland
West of Shetland there are four producing gas fields - Laggan, Tormore, Edradour, and Glenlivet.
Other interests include Breagh - one of the largest natural gas fields developed in the southern North Sea.
INEOS Oil & Gas UK also operates the unmanned Clipper south field off the Lincolnshire coast.
Sir Jim has the fourth-largest chemicals company in the world.
INEOS operates 36 individual business units covering the chemical and oil and gas industries, together with a number of consumer brands.
Operations in Scotland also include an integrated refinery and petrochemicals centre of excellence at Grangemouth. It is the group's largest manufacturing site by volume. Other UK operations include the Forties Pipeline System.
The Telegraph says INEOS has been delving more into oil and gas in recent years to meet demand from its manufacturing plants.
American LNG
Earlier this year, the company struck a major deal to start supplying Europe with American liquified natural gas, in a move it said would provide "much-needed security of supply" at a "critical time for energy markets".
It comes amid accusations that Russia is restricting gas supplies to Europe, cutting flows through the Nord Stream 1 pipeline, to weaponise energy during its war in Ukraine.
There were reports last week linking Sir Jim to a possible bid for Manchester United, but any move would be costly.
The boyhood supporter of the team could have to fork out as much as £5billion to buy one of the most famous football clubs in the world.
Sir Jim wants to initially buy a stake in the Old Trafford side before later taking full control.
A spokesman for the entrepreneur confirmed that he would welcome the chance to talk to the club's American owners, the Glazer family.
The comments follow a report which claims the Glazers are considering selling a minority stake in the club.
Sir Jim, who is 69, is worth an estimated £13.5billion.
In May, he made an unsuccessful £4.25billion offer to buy Chelsea after Roman Abramovich put the London club up for sale.