Britain's richest man Jim Ratcliffe is hoping to extend his grip on the North Sea by buying oil and gas fields from US giant ConocoPhillips.
Mr Ratcliffe's company Ineos and ConocoPhillips have both confirmed that they are in exclusive talks.
Among the assets up for grabs is Conoco's 6.5% stake in the Clair field, west of Shetland.
The field potentially has 7 billion barrels of oil in place, according to BP's chief executive Bob Dudley.
BP recently bought a 16.5% stake in the Clair field from ConocoPhillips, giving the UK oil giant a total holding of 45.1%.
Reports suggest that the assets ConocoPhillips is selling could be worth as much as $3bn (£2.3bn).
They do not include the company's oil terminal in Teesside or its commercial trading group based in London.
The North Sea is still a relatively new area for Mr Ratcliffe and Ineos.
The billionaire, whose £21bn fortune makes him the UK's richest man according to the Sunday Times rich list, has traditionally invested in speciality chemicals businesses.
Ineos owns the Grangemouth oil refinery site in Scotland which manufactures a range of petrochemicals that are used in a wide range of products including bottles, food packaging and in the pharmaceuticals industry.
Ineos first acquired a number of North Sea gas fields in 2015 before it buying up the oil and gas business owned by Denmark's Dong Energy for £1bn two years later.
The Sunday Times reported that Ineos had put down a deposit in exchange for three months of exclusive talks with ConocoPhillips.
Ineos declined to comment.