New York's main contract, light sweet crude for delivery in March, gained 70 cents to $99.37 a barrel. Brent North Sea crude for March delivery added 79 cents to $118.10.

Crude traders breathed a sigh of relief after Greek lawmakers Sunday pushed through a new round of drastic austerity measures despite public protests that left dozens injured and buildings ablaze, analysts said.

"I think this is the key reason that sentiment has turned positive over the weekend," said Ker Chung Yang, commodity analyst for Phillip Futures in Singapore.

Greek Finance Minister Evangelos Venizelos told parliament it had to back the plan to unlock a 130 billion euro ($171 billion) rescue fund from the EU and the International Monetary Fund, or Greece would be forced to default.

The vote, while a key hurdle, will not in itself release the funds. Eurozone finance ministers are set to meet Wednesday in Brussels to discuss the next step.