Energy stocks were lower Tuesday afternoon, with the NYSE Energy Sector Index decreasing 0.5% and the Energy Select Sector SPDR Fund (XLE) down 0.3%.

The Philadelphia Oil Service Sector index was falling 1.2%, and the Dow Jones US Utilities index was up 0.6%.

Front-month West Texas Intermediate crude oil declined 1.5% to $61.77 a barrel, and the global benchmark Brent crude contract fell 1.4% to $65.69 a barrel. Henry Hub natural gas futures slumped 4.4% to $2.76 per 1 million BTU.

In corporate news, Woodside Energy (WDS) shares fell past 4% following its H1 results. Separately, Woodside may retain an up to 80% stake in its $17.5 billion Louisiana LNG project, even as it continues talks with potential partners, including Saudi Arabia's Aramco, The Wall Street Journal reported.

Black Hills (BKH) and NorthWestern Energy (NWE) said Tuesday that their boards have approved a deal to merge their businesses in an all-stock transaction to create a regional regulated electric and natural gas utility company with a combined enterprise value of $15.4 billion. Black Hills shares rose 1%, and NorthWestern jumped past 6%.

Empire Petroleum (EP) shares fell nearly 4% after the company said Tuesday that it has extended the expiration date of its subscription rights offering to raise up to $5 million to Aug. 20.