Rebels from Nigeria's oil-producing Niger Delta said they had blown up a Royal Dutch Shell pipeline, forcing the Anglo- Dutch major to shut some production.
The attack was the latest act of sabotage in a campaign by militants that has cut oil output in the world's eighth-largest producer by around a fifth since 2006.
Nigerian Minister of State for Oil Odein Ajumogobia said in a Nigerian television interview the most recent attacks have lead to shut-ins amounting 175,000 barrels per day but he expected the outage to be restored in the coming weeks Oil output in OPEC producer Nigeria has been erratic in recent months due to repeated rebel attacks to oil facilities and a workers' strike in April.
Ajumogobia also said 470,000 bpd had been shut in even before these latest attacks.
In Europe, Norwegian oil and gas producer StatoilHydro said its Statfjord A field, which produces 19,000 barrels of oil per day, remained shut after an oil leak on Saturday.
Nigeria's Ajumogobia said fear of a future supply shortfall was driving the market.
"I do not think we can say there is a shortage of supply today but I think people perceive a shortage of supply tomorrow and that is what is driving the oil price," he said.
OPEC, the source of more than a third of the world's crude, has not taken united action to raise output, but Saudi Arabia individually has said it will pump more oil.
OPEC President Chakib Khelil reiterated the group would not meet to discuss the oil market until its next scheduled gathering in September, the website of the Libyan National Oil Corporation (NOC) reported on Monday.