Oil prices rallied as traders tracked the weak dollar, better-than-expected economic data and the latest energy inventories report for top energy consumer the US.
Light sweet crude for delivery in April, gained $1 to $80.68 a barrel.
Brent North Sea crude for April climbed 84 cents to $79.02.
The euro shot up against the dollar after Greece announced tough new austerity measures that analysts said opened the door to concrete assistance from the country's European partners.
The single European currency at one point jumped to a two-week high of $1.3729 after Athens unveiled tax hikes and spending cuts designed to save the debt-ridden state €4.8bn and restore Greece's tattered credibility on financial markets.
A weak dollar boosts dollar-priced crude oil because it becomes cheaper for buyers using stronger currencies, which in turn tends to lift demand.
Oil prices had closed higher yesterday, buoyed by a weak greenback which makes dollar-priced crude cheaper for holders of foreign currencies, pushing up demand, traders said.
Meanwhile, Anglo-Dutch oil group Shell reported an attack on its flowstation in southern Nigeria, but said the facility as not producing at the time of the incident.
Local media reported that a previously unknown group calling itself 'the Peoples Patriotic Revolutionary Force' had claimed responsibility for the attack.
Oil is Nigeria's economic mainstay, raking in some 95% of export earnings and accounting for about 85% of budget requirements for the OPEC member country.
