Energy stocks were advancing pre-bell Tuesday, with The Energy Select Sector SPDR Fund (XLE) up 2.8%.

The United States Oil Fund (USO) was up 0.9% and the United States Natural Gas Fund (UNG) was 3.3% higher.

Front-month US West Texas Intermediate crude oil was up 0.6% at $61.07 per barrel at the New York Mercantile Exchange. Global benchmark North Sea Brent crude oil rose by 0.5% to $64.53 per barrel, and natural gas futures were 2.1% higher at $3.73 per 1 million British Thermal Units.

Phillips 66 (PSX) asked its shareholders to reject activist investor Elliott Investment Management's attempt to change the leadership and strategy of the company, according to a definite proxy statement. The company's shares were up over 2% premarket.

Diamondback Energy (FANG) stock was over 3% higher after the company overnight disclosed a proposed resale, from time to time, by selling security holders of up to 6.84 million common shares.

BW LPG (BWLP) shares were up past 5% after the company said it launched a program to repurchase up to 3 million shares for up to $20 million from the open market.