Energy stocks were lower Tuesday afternoon, with the NYSE Energy Sector Index easing 0.1% and the Energy Select Sector SPDR Fund (XLE) down 0.8%.

The Philadelphia Oil Service Sector Index was decreasing 0.2%, and the Dow Jones US Utilities Index fell 1.3%.

Front-month West Texas Intermediate crude oil declined 1.8% to $60.22 a barrel, and the global benchmark Brent crude contract was dropping 1.8% to $64.46 a barrel. Henry Hub natural gas futures were 2.6% lower at $3.35 per 1 million BTU.

In corporate news, Ameren (AEE) is facing a favorable regulatory position and forecasted growth appears fairly priced in stock value, resulting in limited near-term upward revision catalysts, RBC Capital Markets said in a note. RBC started coverage with a sector perform rating. Ameren shares were down 1.3%.

YPF (YPF) is in preliminary talks with Abu Dhabi National Oil Co.'s XRG overseas unit to get an investment for its LNG project in Argentina, Bloomberg reported. YPF shares added 3.3%.

Brookfield Asset Management (BAM) and Cameco (CCJ) shares rose 1.6% and 23%, respectively, after the companies said they have signed an $80 billion partnership with the US government to build new Westinghouse Electric nuclear reactors in the US.