Oil and gas futures rose yesterday as reports of new refinery outages in the United States countered news that Nigerian labor unions ended a strike over the weekend.

Analysts said traders started buying after hearing of problems at two refineries over the weekend, which revived concerns about domestic gasoline supplies. Oil had started the day dropping more than US$1 a barrel and pulling other energy futures lower in response to the strike's end.

Light, sweet crude for August delivery rose 4 cents to settle at US$69.18 a barrel on the New York Mercantile Exchange, while gasoline for July added 1.59 cents to settle at US$2.3025 a gallon. August Brent crude rose 18 cents to settle at US$71.36 a barrel on the ICE Futures exchange in London, The Associated Press reported.

In other Nymex trading, heating oil futures for July rose 0.44 cent to settle at US$2.0424 a gallon while July natural gas prices fell 19 cents to US$6.94 per 1,000 cubic feet.

Futures traders began the day selling on news that Nigerian labor unions called off a strike aimed at overturning a government fuel price hike, ending a four-day work stoppage. The unions accepted a government proposal to raise gas prices by 4 cents a liter -- half of what the government wanted -- in exchange for a government promise to hold prices steady for a year.

Energy futures prices rose sharply last week on worries the unions would follow through on their threat to shut Nigeria's oil industry down, although in the end, oil supplies were not affected. Nigeria is Africa's biggest oil producer and one of the top overseas suppliers to the United States.

Later in the day, investors switched their focus to reports that Exxon Mobil Corp and Lyondell Chemical Co were forced to shut down some gasoline making equipment at refineries in Texas over the weekend, said Andrew Lebow, senior vice president at Man Financial Inc.

"The market reassesses and starts worrying about these refinery problems," Lebow said.

Neither shutdown was major or expected to last long. But in a tight market, any little bit of lost refinery capacity can send prices higher, analyst said.

Last week's inventory report from the Energy Department's Energy Information Administration showed unexpected jumps in oil and gasoline inventories, but a surprising decline in refinery utilization rates. Traders were blindsided by the 6.9 million barrel build in crude stocks, and sent oil prices down by nearly US$1 Wednesday. But the respite was short-lived, as worries about the Nigerian strike and Iranian nuclear enrichment pushed oil up on Thursday and Friday.

The record gasoline prices of recent months were the result of an unusual number of domestic refinery outages this spring. Analysts and traders have long been concerned that the refining industry won't be able to produce enough gasoline to meet US summer driving demand, which peaks between the July 4 and Labor Day holidays. Those fears have been fed by EIA reports that show refinery utilization rates in the 87 percent range, well below the 94 percent to 95 percent range analysts prefer.

Oil prices, which trade in sympathy with gasoline futures, are likely to continue trading in the high US$60 range, said Tom Kloza, publisher and chief oil analyst at the Oil Price Information Service.

"It's hard to find something that you're going to grab onto and say, well, this is going to drive prices higher or this is going to drive prices lower," Kloza said.

Although retail gas prices continue to fall, their pace of decline has slowed, Kloza said. Gas prices aren't likely to continue falling, and could even rise again if the supply picture doesn't improve, analysts said.

"The overall battle goes on -- supplies are so much lower than normal," Flynn said.