Oil prices edged modestly higher Friday as news of an output cut in Nigeria helped to halt, at least temporarily, the week's sharp decline in prices.

Given the market's inability to spark a larger rally Friday following the week's big sell-off, is it time to declare the energy bubble over?

Experts aren't ready to go that far just yet. Oil has bounced back from big drops more than once in its march to fresh records over the past year.

But in a sign sentiments have shifted, the question is being asked more often, even by industry observers who just days ago thought the market's meteoric run still had legs.

"If this is not the bubble's implosion, than it's a reasonable facsimile," analyst and trader Stephen Schork said in his daily market commentary. "Perhaps all we have witnessed was a replay of last August's subprime induced sell-off. Time will tell. Nevertheless, for the time being we no longer care to hold a bullish view."

Light, sweet crude for August delivery rose 59 cents to $129.88 a barrel on the New York Mercantile Exchange. In London, Brent crude futures for September delivery rose 81 cents to $131.88 on the ICE Futures Exchange.

Investors who saw the suddenly discounted crude prices, which tumbled nearly 11% over the past three days, as a buying opportunity also added support the increase.

Friday's relatively modest gains follow a three-day swoon in which oil prices tumbled nearly $16. Just last week, oil hit an all-time high above $147 a barrel.

A Nigerian military official said an explosion that destroyed an Eni SpA oil pipeline in the country's restive southern oil region Thursday was not an accident but "deliberate sabotage" by youth upset about the alleged nonpayment of fees by the energy company to the local population.

Nigeria's major militant group -- the Movement for the Emancipation of the Niger Delta -- had denied any involvement in the blast, which caused a sudden drop in pressure that stopped production on pipelines carrying 47,000 barrels of oil a day.
Eni said in a statement that the causes of the incident were unknown.

Based on how oil prices were developing from the technical point of view, analyst Olivier Jakob of Petromatrix in Switzerland said Nymex futures were "getting into deeper trouble."

"Buying here is an opportunity if you are a deep believer in $200 (a barrel), otherwise we think that caution would be better applied," Jakob said in a research note.

In other Nymex trading, heating oil futures rose 0.31 cent to $3.7469 a gallon while gasoline prices rose 4 cents to $3.2034 a gallon. Natural gas futures rose 7.8 cents to $10.615 per 1,000 cubic feet.