Oil prices nudged back above 67 on Monday with 23 percent of Nigerian output still shut by rebel attacks and no sign of Royal Dutch Shell restarting exports from its vast Forcados oilfield and terminal. The removal of 550,000 barrels per day of Nigerian oil has coincided with growing demand from refiners in the United States, consumer of 40 percent of the world's gasoline. "The loss of critical Nigerian barrels just as U.S. refiners are returning from maintenance has established a $60 floor (for U.S. crude) and threatens to re-test the all time high of $70.85," analysts at PFC Energy wrote in a note. U.S. crude oil was up 44 cents at $67.05 a barrel at 1040 GMT. London Brent was up $1.20 at $67.11. Nigerian Minister of State for Petroleum Edmund Daukoru told reporters on Monday the biggest foreign operator Shell would restart its offshore 115,000 bpd EA field in days. There was no immediate comment from Shell. Nor was there any sign of its more important onshore Forcados oilfield restarting. Reuters reported on Sunday that Shell was reluctant to send its staff back into the violent southern delta region despite more naval patrols there. Deutsche Bank noted many analysts expected attacks on Nigeria's oil industry to continue in the run-up to the presidential election early next year. U.S. oil hit a $70.85 record high last September after hurricanes knocked out a big chunk of Gulf of Mexico refining and oil and gas production. Analysts say another active U.S. hurricane this year could strain the oil market still further. IRAN On Friday Iranian Foreign Minister Manouchehr Mottaki was the latest Iranian official to vow that the world's fourth-largest oil exporter would not use oil as a weapon as it faces a U.N. Security Council rebuke over its nuclear research. But the assurance did not entirely calm market nerves. "No one is willing to assume Iran will never use oil as a bargaining chip," said Tobin Gorey, commodity analyst at Commonwealth Bank of Australia. Despite a dip in prices on Friday after Mottaki's remark, oil rose 3.7 percent last week amid an influx of fund money into commodities and a big draw in weekly U.S. gasoline inventories. OPEC, which agreed a month ago to carry on pumping near a 25-year high to offset supply concerns, appeared to have little choice but to carry on that policy. "The price as it is now, nothing will happen" at OPEC's next scheduled meeting in June, Qatari Oil Minister Abdullah al-Attiyah said on Sunday. "We are doing all that we can do... to stabilise the oil market." PFC Energy analysts agreed. "Unless the Nigerian outages can be fixed, OPEC will be in a bind again," they wrote.