NEW YORK, Oct. 29 (Xinhuanet) -- Crude oil futures gained Friday as traders worried that labor unrest in Nigeria might cause fresh supply disruptions.

    On the New York Mercantile Exchange, crude oil for December delivery rose 86 cents to settle at 51.76 dollars a barrel. On London's International Petroleum Exchange, the December Brent crude-oil futures contract gained 61 cents to end at 48.98 dollars per barrel.

    The main labor body in Nigeria, the sixth-largest OPEC crude producer, said a general strike was likely after it rejected a plan to quell anger over fuel prices in the country.

    "What the government has done is to do nothing, therefore labor will meet with its coalition allies on Sunday and announce the date of a fresh strike," Owei Lakemfa, spokesman for the Nigeria Labor Congress Agence France Press.

    "Everybody's just so nervous at this point with the Nigeria situation," said an American oil broker.

    In a research report, economists at Citigroup Global Markets Inc. said the surging energy prices might increase consumer's fuel bills by 60 billion dollars and might subtract as much as 0.9 percentage point from fourth-quarter growth.

    The Commerce Department said Friday that GDP rose 3.7 percent for third quarter, less than the 4.3 percent rise economists had expected. Enditem