Energy stocks rose Monday afternoon, with the NYSE Energy Sector Index up 0.7% and the Energy Select Sector SPDR Fund (XLE) adding 0.8%.

The Philadelphia Oil Service Sector index shed 1.2%, and the Dow Jones US Utilities index advanced 1.3%.

West Texas Intermediate crude oil declined 1.2% to $66.22 a barrel, while global benchmark Brent fell 1.2% to $69.52 a barrel. Henry Hub natural gas futures rose 2.8% to $4.52 per 1 million BTU.

In sector news, the Ontario government informed representatives of New York, Michigan and Minnesota that the province is imposing a 25% surcharge on electricity exports to the states in response to President Donald Trump's tariffs on Canada, Ontario Premier Doug Ford said.

Separately, the US Supreme Court denied a bid by Alabama and 18 other states for leave to file a complaint against five other states seeking to hold private companies liable for allegedly deceiving the public about the dangers of using their fossil-fuel products.

In corporate news, Veren (VRN) and Whitecap Resources agreed to merge in an all-stock deal worth 15 billion Canadian dollars ($10.39 billion) to create the largest Canadian light oil-focused producer. Veren shares jumped 14%.

Sunnova Energy International (NOVA) shares rose 5.5%. The company named Paul Mathews as chief executive officer.

Petrobras (PBR) finalized a $283 million agreement to end a legal dispute in the US involving EIG Energy Fund XIV. Petrobras shares fell 1.9%.