Profits increased at CNR International last year as the Canadian firm stepped up production.
CNR said it achieved record annual production of about 1.08 million barrels of oil equivalent per day (boepd), 12% higher than in 2017.
Revenues increased by about a fifth to £11.9 billion, while pre-tax profits climbed to £2bn from £1.6bn.
In the North Sea, the firm pumped out 23,965 boepd in 2018, up 2% year-on-year, as a successful drilling program was partially offset by natural field declines.
CNR drilled 3.9 net producer wells during the 12 months. Current oil production remains “strong” at about 1,250 barrels per day net from each well.
The North Sea drilling campaign for 2019 includes 3.9 net producer wells and got under way in the first quarter at the Ninian South Platform.
UK operating costs averaged $39.89 per barrel last year.
CNR has North Sea proven reserves of 124 million barrels.
Its interests include the Ninian, Lyell and Columba fields in the northern North Sea, and the Banff, Kyle, Tiffany, Toni and Thelma fields in the central North Sea.