Britain's Rolls-Royce Motor Cars Ltd. is reportedly in talks to buy the marine propulsion unit of Finnish power plant and ship engine maker Wartsila.

Reuters, citing an earlier report by Bloomberg, said that Wartsila may however oppose the sale. The Finnish corporation has refused other approaches for its marine propulsion unit, where it sees potential fro growth.

Wartsila's ship power unit accounted for 28% of the group's net sales in 2012, the report said.

Rolls-Royce has lowered its profit guidance for its marine business in November from modest growth to broadly flat. It has generated 18% of its 2012 revenue from the marine division. Rolls-Royce is the world's second-largest maker of aircraft engines behind US conglomerate General Electric, Reuters said.

BBC in an earlier report said that Rolls-Royce saw its 2012 revenue grow 8% to £12.2 billion. Its underlying pre-tax profit rose 24% to £1.4 during the same year, led by a strong performance in its civil aerospace division.