Ineos has completed its $250m (£199m) acquisition of the Forties Pipeline System in the North Sea from BP.
The energy giant now controls the system responsible for delivering close to 40 per cent of the UK's oil and gas from the North Sea.
The 235-mile pipeline connects 85 North Sea oil and gas assets both to the mainland and to Ineos' site in Grangemouth.
This summer, Ineos unveiled plans for a major expansion at its plants in Scotland and Norway.
The petrochemicals firm is increasing the ethylene capacity of its facilities at Grangemouth in Scotland and Rafnes in Norway to over 1m tonnes each, adding up to 900,000 tonnes of ethylene to its overall production capacity.
Grangemouth is Ineos' largest manufacturing site, and its ethylene cracker is one of only four of its kind in Europe.