Oil rose, pushing Brent as high as US$40.11 earlier in the day, climbing above US$40 for the first time since December. The global crude benchmark traded at US$39.92 in late morning trading in New York.
Shares of Chevron and those of Exxon Mobil also gained, trading 2.7 percent and 2.3 percent higher in early afternoon in New York.
"Money flows from broader financial markets are powering this broader rally in oil," Scott Shelton, energy broker with ICAP in Durham, North Carolina, told Reuters. "I don't think the energy fundamentals for the next few days are going to matter much as the market is making a transition."
US Treasuries fell, as a string of stronger-than-expected economic data realigned expectations on the outlook for interest rates. While 50 of the 60 economists polled by Bloomberg expect the Federal Reserve to leave rates unchanged at its next policy meeting March 15-16, traders have boosted bets it will lift rates later this year.
In Europe, the Stoxx 600 Index ended the session with a 0.3 percent drop from the previous close. The UK's FTSE 100 Index fell 0.3 percent, as did France's CAC 40 Index, while Germany's DAX Index declined 0.5 percent.
Germany bunds rose, amid expectations European Central Bank policy makers will announce extra stimulus including a deposit rate cut after their meeting ends on Thursday.
"People are now taking profits after a decent run in the last weeks," Konstantin Giantiroglou, head of investment advisory and research at Neue Aargauer Bank in Brugg, Switzerland, told Bloomberg. "Economic data will become the dominant factor as everything looks so fragile, especially now ahead of ECB. The market expects the ECB to do something."
Shares of Valeant Pharmaceuticals jumped, last up 9.9 percent, after the company said it would release preliminary quarterly results and guidance on March 15. Last month Valeant cancelled an investor call, delayed the release of its financial statements and withdrew its prior financial guidance.