Brent crude was up 64 cents, or 1%, at US$63,98 a barrel by 04h13 GMT.
Ineos, which operates the Forties pipeline system in the North Sea, said Wednesday it was reviewing a range of options to fix cracks in a system that carries about 40 percent of total regional production, or about 450,000 barrels per day.
"At this stage it is still too early to say how long the fix will take to complete, but it is expected to be a matter of weeks rather than days", Ineos said, adding that a number of fix options were now being assessed and developed.
The Forties pipeline system, which was built by BP in 1975 as one of the largest in the North Sea, is about 100 miles long and transports around 450,000 barrels of oil a day, which is about 40 per cent of United Kingdom production.
This poses challenges for OPEC's hope of draining global stocks. If the Forties pipeline is "out for a month, it should have a positive effect" on prices as 10 million barrels of supply could easily be lost to the market.More news: Apple invests $390 million in VCSEL maker Finisar
The Forties pipeline was sold-off by BP to Ineos only six weeks ago in a sale which rankled critics of the privately-owned company.
At the same time, OPEC is upbeat about the massive drawdowns in recent months.
Global oil supply rose in November at the fastest rate in a year amid a surge in USA shale production, possibly complicating OPEC's efforts to restrain output. Stocks fell by 5.1 million barrels in the week to December 8, the fourth consecutive week of decline, to 442.99 million barrels, the lowest since October 2015.
The gravity of the Forties outage was magnified by an explosion one day later at a key hub for Russian gas imports into Europe.
The main impact on the Brent futures is the surge for contracts for deliveries in February and March, Reuters market analyst John Kemp notes. Early on Thursday, the Brent premium over WTI was just below $6 a barrel.
"Brent crude raced higher ... as news broke that the North Sea's Forties Pipeline system would have to be shut down for a "number of weeks" after a hairline crack was found in it", said Jeffrey Halley, senior market analyst at futures brokerage OANDA in Singapore. This outage may accelerate the pace of shrinking global inventories and give OPEC's efforts an unexpected boost.