Energy giant Ineos has struck a deal to acquire the Forties Pipeline System in the North Sea from BP for $250 million (£199 million).

The transaction, which also includes the Kinneil Terminal, will see Ineos take control of a system that delivers almost 40% of the UK’s North Sea oil and gas.

The Forties pipeline was opened in 1975 by BP and now consists of more than 100 miles of pipes with the capacity to transport 575,000 barrels of oil a day from UK fields in the North Sea (plus several Norwegian fields).

Ineos chairman and founder Jim Ratcliffe said: “The North Sea continues to present new opportunities for Ineos. The Forties Pipeline System was originally designed to feed the Grangemouth refinery and petrochemical facilities. We have a strong track record of acquiring non-core assets and improving their efficiency and reliability, securing long-term employment and investment.”

BP chief executive Bob Dudley said: “While the Forties pipeline had great significance in BP’s history, our business here is now centred on our major offshore interests west of Shetland and in the Central North Sea.”

The Forties pipeline employs around 300 BP staff at Kinneil, Falkirk, Dalmeny, Aberdeen and offshore.

Speaking of the deal, Unite Scottish secretary Pat Rafferty said: “It’s not so long ago that both Grangemouth and the Forties pipeline were owned by all of us and operated by a nationalised British Petroleum, with a responsibility to look at what was good for the country as a whole.

“Both these parts of vital national infrastructure, which are central to the success of the Scottish and wider UK economy, are now essentially in the hands of one man. Unite firmly believes that this sale is bad for Scotland and for the UK.”

Responding to these criticisms, John McNally, Ineos transition manager for the deal, said: “We are the fourth-largest petrochemical company on the planet. We got there by treating our customers and suppliers with respect and working hand-in-hand with the regulators and the government agencies in all the countries where we work.

“We plan to have a very good relationship with the UK Government, the customers of the Forties Pipeline System and our suppliers. I think this is an excellent deal, and I think Ineos have skills that can actually secure longer-term jobs here than other companies could.”

Mr McNally also reassured the almost 300 staff who work on the pipeline system throughout Scotland that he has no plans for redundancies.