Oil prices climbed towards $41 a barrel on Tuesday after OPEC signaled it might deepen its record output cuts to help boost prices and drain bloated stockpiles.

OPEC’s president told Reuters the group could take more action when it meets on March 15. Later, an OPEC source said the group may discuss a 1 million barrel-per-day cut in addition to the 4.2 million in reductions agreed since September.

U.S. light crude for March delivery rose 73 cents to $40.81 by 1730 GMT, having fallen to $39.83 on Monday, the first time below $40 a barrel in three weeks. London Brent rose 53 cents to $44.35.

“Prices do seem to have bottomed for now,” said Kevin Norrish of Barclays Capital. “OPEC has probably taken more than enough off the market and there’s a risk of over-tightening, in which case prices would go back up fairly swiftly.”

Slowing economic growth in the United States, China, Japan and other major consumers has dampened fuel use, swelled stocks and knocked more than $100 a barrel off the price of crude since its July 2008 peak near $150.

But despite the softening world energy demand, oil has held stubbornly above the $40 mark in recent weeks, buoyed partly by the aggressive OPEC cuts.

A Reuters survey showed the group, which pumps a third of the world’s oil, had carried out about 67 percent of its record curb in January.

Adding support to prices Tuesday were oil worker labor disputes in the United States, Europe and Nigeria — though none had hurt supplies yet.

Negotiators were hashing out a contract for U.S. refinery and pipeline workers and the union has said it could strike if talks break down — a move that would shut some 10 percent of the nation’s fuel production capacity within days.

In Europe, hundreds of contract workers at British energy facilities were protesting the use of foreign workers, though operations at refineries, power plants and pipelines remained unaffected.

Nigeria’s senior oil workers’ union, meanwhile, threatened to begin an indefinite strike from Monday unless the government improved security in the Niger Delta, its restive oil heartland.

Nigeria pumped about 1.75 million barrels per day (bpd) in January, versus its OPEC supply target of 1.67 million bpd, according to the Reuters survey.

U.S. crude inventory data were likely to show stocks rose for the sixth time in a row as refinery utilisation remained curbed by seasonal maintenance and imports rose, according to a Reuters poll of analysts.

Analysts issued their forecasts ahead of weekly inventory data to be released on Wednesday by the U.S. Energy Information Administration. Industry group American Petroleum Institute will release its data on Tuesday.

LONDON, Feb 3 (Reuters)