Oil prices are strengthening after Russia pounded Ukrainian energy targets, hours after President Trump declared an "energy ceasefire" between the two countries.
Diesel futures have also pared their declines and turned higher. A supply deal with Russia struck last week would likely have a limited effect on prices. Traders are also on edge about the Middle East, where Iran-backed Houthi militants carried out lethal strikes on Saudi Arabia's main airport over the weekend.
U.S. stocks are trading mixed, with the Dow industrials higher and the Nasdaq composite lower. U.S. bond markets are closed for Columbus Day, marked by some as Indigenous Peoples' Day.
Looking ahead, earnings season will kick into gear with results from big U.S. banks starting tomorrow. Also in focus: consumer inflation data due on Wednesday, and a public appearance by Fed Chairman Kevin Warsh on Thursday at a summit being held in Bangkok by the IMF and the World Bank.