U.S. crude gained over 5 percent Monday as investors rotated more assets into raw materials and oil buying was encouraged by talk that OPEC producers want a higher anchor price.
Oil prices also got a boost from data showing a smaller-than-expected build in stockpiles at the Cushing, Oklahoma delivery hub for U.S. crude futures. But some analysts cautioned that the global crude glut remained large.
Global crude prices have risen more than 40 percent since hitting 12-year lows less than two months ago. The rebound has also been driven by chart-related buying and asset rotation by investors, which resulted in higher allocations into commodities such as oil and metals, as well as equities.
U.S. equities have risen about 8 percent since mid-February. Asian stock markets hit two-month highs.
"Money flows from broader financial markets are powering this broader rally in oil," said Scott Shelton, energy broker with ICAP in Durham, North Carolina. "I don't think the energy fundamentals for the next few days are going to matter much as the market is making a transition."