A conservative group is hitting billionaire environmentalist Tom Steyer for dividing the Democratic Party between labor unions and environmental groups with a new ad being pushed on Facebook.

AR Squared, the policy arm of America Rising, released the ad Wednesday as part of its latest hit on Steyer. The group announced in April it would be treating Steyer’s environmental agenda with scrutiny usually reserved for a presidential candidate, and the accusations of dividing the Democratic Party are the latest push.