The Forties Pipeline System is likely to be closed for weeks while operator Ineos carries out repair work, a spokesman for the company said.

The pipeline, which carries around 450,000 barrels per day of Forties crude from the North Sea to the Kinneil processing terminal in Scotland, had been operating at reduced capacity since December 7 when a routine inspection revealed a small leak.

One trader said shipments of Forties would inevitably be affected by the closure.

Petroineos, the refining arm of Ineos, owns the 200,000 barrel-per-day Grangemouth refinery and bid for January-loading Forties at a premium of 60 cents to dated Brent, the highest in nearly four months.