Perfect storm for lower oil prices U.S. West Texas Intermediate crude ended the session at US$50.28 per barrel, down US$2.86, or 5.38 per cent after falling to its lowest level since Dec. 15.
Brent crude slumped to its lowest level since Dec. 8 at US$52.93, before settling at US$53.11, down US$2.81 or 5.03 per cent.
Both contracts also fell below their 100-day moving averages for the first time since late November, when the OPEC supply cuts were announced.
"This is one of those occasions where the news follows the trend and we've now tried for the better part of the year to get through the US$55-$56 area for WTI specifically and we've failed," said Brian LaRose, technical analyst at ICAP in Jersey City, New Jersey.
"This is more of a catalyst and a wake-up call to a lot of people to say here's some fundamentals to back up what technicals have been saying for the last three weeks."
Key support levels for WTI to watch are the US$51-$50 range heading to the end of the week, which are being tested in Wednesday's session, LaRose said, adding that if breached, the next levels to watch would be the US$47-$48 range.
Also pressuring oil prices were expectations of a U.S. interest rate hike next week, which lifted the dollar against a basket of currencies, making greenback-denominated oil more expensive for holders of other currencies.