Oil climbed to a near one-month high on Wednesday on signs of a gradual tightening in global oil inventories and on concerns about a supply outage at a field in the United Kingdom's North Sea that feeds into an international benchmark price.
Brent crude futures were at $54.52 per barrel, up 35 cents or 0.65 percent from their last close.
U.S. West Texas Intermediate (WTI) crude futures were up 33 cents, or 0.65 percent, at $51.35 a barrel.
Both benchmarks hit their highest levels on Wednesday since March 8.
"The immediate reason for the move was an unplanned production outage in the North Sea," said Sukrit Vijayakar, director of energy consultancy Trifecta, referring to an unplanned production outage at the Buzzard oil field in the North Sea.
Buzzard, being the largest contributor to the Forties crude stream, produces about 180,000 barrels per day. It is a key component of the physical Brent oil price that the Brent futures contract settles against.
Traders also said that prices gained amid slowly tightening market conditions, with the Organization of the Petroleum Exporting Countries (OPEC) leading an effort to cut output.
But the tighter markets will only gradually lead to a reduction in bloated inventories as production especially the United States is rising.
U.S. crude stocks fell by 1.8 million barrels last week to 533.7 million, still near an all-time record, the American Petroleum Institute reported late on Tuesday.
The U.S. rig count rose for an 11th straight week last week to 662, making the first quarter of 2017 the strongest quarter for rig additions since mid-2011, according to energy services firm Baker Hughes.
Following a slump in 2015 and 2016, U.S. oil production has risen 8.5 percent since mid-2016 to 9.15 million bpd, the same level output stood at in 2014, when the market downturn began.