Oil futures prices fell Monday amid concerns about economic growth and on profit-taking ahead of the November contract's expiration. News of a possible ceasefire between Turkey and Kurdish rebels in Iraq added to the selling.

The stock market's sharp downturn Friday has reignited concerns that the economy might be slowing, cutting demand for oil and petroleum products.

But traders are also selling to lock in profits from a rally in which oil futures jumped almost 14 percent in less than two weeks. The November crude contract, which expires Monday, is trading more than $1.20 higher than the December contract. November crude reached a record $90.07 a barrel on Friday morning before declining to settle lower.

"You get to $90, and people say 'Here's a nice chance to take some profit,'" said Kevin Saville, managing editor for the Americas energy desk at Platts, the energy research arm of the McGraw-Hill Cos.

Prices were already down sharply in morning trading when Iraq's president announced that Kurdish rebels will announce a cease-fire Monday night; the news added to crude's decline. Oil prices rose last week in part on concerns that Turkish forces would enter Iraq in search of Kurdish rebel bases. Crude traders worried the move would cut oil supplies from northern Iraq.

Earlier Monday, the Turkish military said eight of its soldiers were missing and 12 dead after an ambush by Kurdish rebels.

Light, sweet crude for November delivery fell $1.92 to $86.68 a barrel on the New York Mercantile Exchange. Before the Iraqi announcement, the contract was down about $1.60.

Other energy futures followed crude lower. November gasoline fell 4.90 cents to $2.1197 a gallon, and November heating oil fell 2.84 cents to $2.3022 a gallon.

November natural gas fell 20.9 cents to $6.832 per 1,000 cubic feet. Natural gas prices are under pressure from unseasonably warm temperatures in the north and Midwest and a forecast that this winter will be warmer than normal.

In London, December Brent crude dropped $1.27 to $82.52 a barrel on the ICE Futures exchange.

Analysts are beginning to debate whether last week's foray by crude futures above $90 a barrel marked the peak of the bull market. Analysts are similarly split over whether the underlying supply and demand fundamentals justify such high prices.

Predictions about the future of oil prices range from $60 to $120, depending on whether the analyst believes forecasts oil supplies will tighten amid growing demand in the fourth quarter. Many analysts think prices have risen sharply in recent weeks due to speculative investing. Indeed, data released on Friday shows speculative buying of oil contracts increased last week.

But other analysts argue that the fundamentals clearly support higher prices.

"The bashing of speculators in the oil market by uninformed and biased watchers of the energy prices and energy markets is the new sport for those that still are in denial about the real fundamentals facing the market," wrote Phil Flynn, an analyst at Alaron Trading Corp., in Chicago, in a research note.

The demand side of the oil fundamentals equation could be affected by an economic slowdown. Some investors worry Friday's sharp drop in the stock market reflects an overall cooling in the economy.

At the pump, meanwhile, gasoline prices continued their delayed reaction to the recent increase in oil prices. The national average price of a gallon of gas rose 0.2 cent overnight, to $2.819 a gallon, according to AAA and the Oil Price Information Service.

Gas prices have jumped 6.2 cents over the last week. Many analysts expect gas prices to move even higher to catch up with crude prices.