Oil rose to around $57 a barrel on Monday as traders saw the previous session's near 4 percent fall as excessive and violence in Africa's top oil exporter Nigeria lent support.

Nigeria's main militant group said it would blockade key waterways in the Niger Delta to try to prevent crude exports. On Sunday, militants said they had blown up two oil and gas pipelines.

U.S. crude for June rose 66 cents to $57.00 by 0936 GMT (5:36 a.m. EDT). It fell $2.28 to settle at $56.34 on Friday, down from a six-month high above $60 hit earlier last week. London Brent crude for July rose 82 cents to $56.80.

There was quite a pullback on Friday and it might have been a bit overdone, said Rob Montefusco, a broker at Sucden Financial. The whole Nigerian situation is quite supportive at the moment, he added.

The June U.S. crude contract expires on Tuesday and dealers said trading may be more volatile than usual as a result.

Later on Monday, data on U.S. homebuilder sentiment and sales will give an indication how the world's largest economy is faring. Confidence at Japan's manufacturers edged up from record lows, a Reuters monthly poll showed.

European stocks rose slightly on Monday, following on from losses in Asia.

OPEC, which has agreed to cut 4.2 million barrels per day (bpd) of output since September, meets on May 28 to decide production policy. So far, OPEC comments suggest the group is unlikely to cut supply further.

Kuwait's oil minister told Reuters there was no need for further output cuts by the Organization of the Petroleum Exporting Countries, as he did not want to see oil prices go up too fast.

OPEC's supply curbs have helped oil recover from a near five-year low of $32.40 reached in December. The market has also tracked a rally in equities underpinned by hopes of an economic recovery.

Crude oil speculators on the New York Mercantile Exchange shifted to a small net long position in the week to May 12, according to data from the U.S. Commodity Futures Trading Commission.

In a development that may support gasoline, Sunoco Inc said on Monday production at its 178,000-bpd Marcus Hook refinery on the Pennsylvania-Delaware border was impacted by a fire after explosions at the plant.

(Reporting by Alex Lawler and Fayen Wong in Perth; Editing by Anthony Barker)

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