"It's impossible to call a bottom point, which could, as a result of oversupply and the economics of storage, fall well below $40 a barrel for WTI [West Texas Intermediate], perhaps as low as the $20 range for a while," Citigroup global head of commodity research Edward Morse said, Bloomberg reported.
The pessimistic forecast is explained by a large oversupply on the market and considerable stockpiles of crude, according to the report. US oil production is rising, while production levels in Brazil and Russia are also at record levels.
Saudi Arabia, Iraq and Iran have been cutting oil prices in their struggle for market share in Asia, according to the report.
Prices should bottom out at the start of the second quarter of 2015, and then the market could see a rebound due to shrinking stockpiles, the report suggested.
Since June 2014, global oil prices have fallen by around 50 percent. The Organization of the Petroleum Exporting Countries (OPEC) in November 2014 decided not to cut oil output levels, which contributed to a further drop in prices. The WTI oil price which stood at around $100 per barrel in June, is currently hovering around $50 per barrel.