Brent crude oil hit a fresh five-year low close to $60 a barrel on Monday after producer group OPEC restated its determination not to cut output despite a global fuel glut, but the North Sea benchmark later rallied to around $63.

Market momentum appeared to be downwards, with analysts saying oil could plumb new depths before a sustained recovery.

Oil prices have collapsed over the last six months as high-quality, light crude from North America has overwhelmed demand at a time of lacklustre global economic growth.

The Organization of the Petroleum Exporting Countries has kept production steady, worried that any reduction in its output would have little impact on price and instead mean surrendering market share.

"The decision has been made. Things will be left as is," OPEC Secretary-General Abdullah al-Badri told a conference in Dubai on Sunday. "We agreed that it is important to continue with production (at current levels) for the ... coming period."

Brent for January LCOc1 fell to a low of $60.28 a barrel in Asian trade, down $1.57 and its lowest since July 2009. The futures contract then rallied to trade around $62.85 by 1015 GMT, up $1.00.

U.S. crude for January CLc1 was trading at $58.50 a barrel, up 69 cents, after hitting a low of $56.25 earlier in the day - its weakest level since May 2009.

Analysts said Monday's bounce was partly speculative buying, and partly a reaction to news that Libya's two biggest oil ports had shut due to fighting between armed factions allied to the country's two rival governments.

"The market may just have moved down too far too quickly today," said Tamas Varga, energy analyst at London brokerage PVM Oil Associates. "It was a bit overdone and people may be 'bottom-picking'."

Analysts have cut oil price forecasts sharply over the last few weeks.

"Oil prices may move below $60 per barrel in the near term," analysts at Barclays Bank said, but added that "this (level) is not sustainable in the long run".

Barclays said it expected Brent to average $67 per barrel in the first half of 2015 and $78 in the second half of next year.

National Australia Bank said on Monday it cut its Brent forecast to $80 in the fourth quarter of 2014, $75 in the first quarter of 2015 and an average of $80 for all of next year.