Oil prices remained in a downbeat mood during their final Asian-hours trading session of 2015 after record US crude inventories reinforced concerns about a global supply glut that has pulled down prices by a third over the past year.
Crude inventories in the United States rose 2.6 million barrels last week, the US Energy Information Administration said.
Analysts polled by Reuters had expected a draw of 2.5 million barrels. Crude prices held losses after falling more than 3 per cent in the previous session, with US West Texas Intermediate (WTI) crude futures trading around $36.70 per barrel at 0300 GMT on Thursday and Brent around $36.60 per barrel.
Both benchmarks are down by around a third over 2015.
The immediate outlook for oil prices remains bleak, with some analysts like Goldman Sachs saying prices as low as $20 per barrel might be necessary to push enough production out of business and allow a rebalancing of the market. US bank Morgan Stanley said in its outlook for next year that "headwinds (are) growing for 2016 oil."
The bank cites ongoing increases in available global supplies, despite some cuts by US shale drillers in particular, as well as a slowdown in demand as the main reasons.
"The imbalance in the global oil market has been diminishing in 2H15, but the hope for a rebalancing in 2016 continues to suffer serious setbacks," the bank said, reflecting a market consensus that meaningfully higher prices are not expected before late 2016.
Traders expect some US oil to be taken out of America and supplied into global markets, following the surprise lifting of a decades-old U.S. crude export ban in December, which ended a years-old discount in US crude prices to international Brent.
"At a time when US shale is facing headwinds due to the collapse in crude oil prices... US crude oil exports are likely to help reduce congestion concerns in the US," ING bank said.
Oil prices began falling in mid-2014 as ballooning output from the Organization of the Petroleum Exporting Countries (OPEC), Russia and U.S. shale drillers started to outpace demand.
The downturn gained pace at the end of 2014 after a Saudi-led OPEC decided to keep production high to defend global market share rather than cut output to prop up prices. A year on and the oil downturn has turned into a rout with Brent prices briefly falling below $36 per barrel to levels last seen in over a decade, effectively wiping out the gains from a decade-long commodity super-cycle sparked by China's unprecedented energy demand boom.
The downturn has caused pain across the energy supply chain, including shippers, private oil drillers and oil-dependent countries from Venezuela and Russia to the Middle East. Analysts estimate global crude production exceeds demand by anywhere between half a million and 2 million barrels every day. This means that even the most aggressive estimates of expected US production cuts of 500,000 bpd for 2016 would be unlikely to fully rebalance the market. Russia and OPEC are so far showing few signs of reining in production, leading traders to establish record high active short positions in the market that would profit from further crude price falls.