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PERTH, April 28 (Reuters) - Oil struck a record high at $119.93 a barrel on Monday, extending the previous session's rally, as a strike closed a major British oil pipeline and as fresh violence in Nigeria reignited supply fears.
Simmering geopolitical tensions between the United States and Iran also helped boost oil prices.
U.S. light crude for June delivery <CLc1> rose 81 cents to $119.33 by 2249 GMT, after striking a lifetime high of $119.93 a barrel at the start of Globex electronic trade.
U.S. oil settled $2.46 higher at $118.52 a barrel on Friday.
London Brent crude <LCOc1> rose 66 cents to $117.
"Supply side concerns underpinned the oil price," David Moore, a commodity strategist at the Commonwealth Bank of Australia, said in a note to clients.
"Oil supplies from Nigeria have been disrupted by militant attacks and a strike by some oil workers. A strike at the Grangemouth refinery in Scotland has caused significant disruption to supplies from the North Sea," he said.
A pipeline carrying nearly half of Britain's oil was closed on Sunday as a strike over pensions began at the neighbouring Grangemouth refinery in Scotland, operator BP <BP.L> said. [
]The refinery, owned by international chemical company Ineos, produces a tenth of Britain's petrol and diesel but also supplies vital steam to BP's Kinneil plant that starts to process the crude oil coming ashore from 70 North Sea fields.
In Nigeria, unidentified gunmen killed five policemen and seized several weapons in a raid on a police station in the oil-rich southern Nigerian state of Rivers on Sunday, a police spokeswoman said.
The attack comes just two days after a strike and attacks by rebels forced Nigeria's two largest oil firms, Exxon Mobil <XOM.N> and Royal Dutch Shell <RDSa.L>, to shut in some production.
A step up in tensions between U.S. and the world's fourth-largest crude exporter Iran also contributed to oil's gain.
A cargo ship hired by the U.S. military fired warning shots at boats suspected to be Iranian, the U.S. Navy said on Friday, underscoring tension in the Gulf as the Pentagon sharpened its warnings to Tehran. [
]Iran denied there had been any confrontation between its forces and a U.S. ship, Iranian media reported. [
]Iran also said on Sunday a "disastrous situation" facing the United States in Iraq and Afghanistan, coupled with Washington's domestic issues, made any U.S. attack on the Islamic Republic unlikely. [
]Tensions between Washington and the OPEC nation last year helped send oil to record highs. Crude prices have surged more than five-fold since 2002 as supplies struggle to keep pace with rising demand in emerging economies, such as China.
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] Oil prices as of 2248 GMT Contract Mnth Price Change Day ago pct MA-20* NYMEX Contracts US Crude JUN8 $119.33 +0.81 +$2.46 +2.12% $111.40 Heat Oil MAY8 332.00 +1.72 +4.45 +1.37% 317.25 RBOB MAY8 306.55 +1.18 +3.51 +1.16% 285.63 Natgas MAY8 $11.047 +0.084 +$0.173 +1.60% $10.174 ICE Contracts Brent JUN8 $117.00 +0.66 +$2.00 +1.75% $109.41 Gasoil MAY8 $1089.00 +3.25 +$9.50 +0.88% $1017.60 Note: U.S. heating oil and RBOB gasoline contracts listed in cents per gallon. * = 20-day moving average for continuation month. (Reporting by Fayen Wong)