Energy stocks were declining premarket Monday, with the State Street Energy Select Sector SPDR ETF (XLE) 0.6% lower.

The United States Oil Fund (USO) was down 1.9% and the United States Natural Gas Fund (UNG) was marginally lower.

Front-month US West Texas Intermediate crude oil was 1% lower at $90.20 per barrel at the New York Mercantile Exchange. Global benchmark North Sea Brent crude oil gained 0.2% to reach $102.49 per barrel, and natural gas futures were up 0.5% at $3.05 per 1 million British Thermal Units.

Cenovus Energy (CVE) has agreed to acquire Athabasca Oil at an implied enterprise value of 5.70 billion Canadian dollars ($4 billion), the company said. Cenovus Energy stock was down more than 1% pre-bell.