Crude futures remained on track for weekly losses on Friday as investors reassessed U.S. data on oil stocks and excesses in oil products in Europe and Asia.
While many expect global oversupply of oil to ease in the near term, huge amounts of crude are languishing in vessels at sea and storage tanks on land as the rebalancing takes longer than some had anticipated.
"The narrative of a balanced oil market (in the second half of 2016) has so far been an illusion," UBS oil analyst Giovanni Staunovo said.
"Supply might actually increase in the near term with the further return of disrupted production and higher Middle East production, while demand growth is set to slow in emerging Asia."
Brent crude fell to a more than two-month low of less than $46 per barrel, but were trading at $46 as of 1329 GMT, down 20 cents. The contract closed 2.1 percent lower in the previous session, and is on track for a decline of more than 2.5 percent for the week.
U.S. West Texas Intermediate traded as low as $44.25 a barrel and was currently fetching $44.52, down 23 cents from the previous close. It ended Thursday down 2.2 percent and is on track to close the week also more than 2.5 percent lower.
"It's been pretty volatile," said Richard Mallinson, analyst
with Energy Aspects, adding that low trading volumes in Europe during the summer holidays can "accentuate swings even if there isn't a major catalyst".
Iraq's oil exports are set to rise in July, according to loading data and an industry source, putting supply growth from OPEC's second-largest producer back on track after two months of decline.
Falling prices in the United States have also encouraged traders to send U.S. oil to Europe, adding to supply in the region.
This has helped counterbalance disruptions in Nigeria, where two of the largest crude streams are under force majeure and pipeline attacks have cut some 700,000 barrels per day from production, according to state oil firm NNPC.
While U.S. production has been falling, crude inventories are at 519.5 million barrels, historically high for this time of year, the government's
Energy Information Administration said this week.
Inventories of oil products have also been climbing worldwide. Data
from energy consultancy FGE on Friday showed that oil product stocks in the United States, Europe's Amsterdam-Rotterdam-Antwerp hub and Singapore posted a second consecutive build this week of 2.35 million barrels.
(By Libby George, Additonal reporting by Keith Wallis in Singapore)