 In July 2019, Daines co-founded the Roosevelt Conservation Caucus, a group of Republican members of Congress meant to focus on environmental issues with specific priorities including reducing water and ocean plastic pollution, and heightening access to public lands and waters in the United States for outdoor recreation, hunting and fishing.In January 2019, Daines was one of eleven Republican senators to vote to advance legislation intended to block President Trump's intent to lift sanctions against three Russian companies.In June 2019, Daines was one of eight senators to sign a letter to Premier of British Columbia John Horgan expressing concern over "the lack of oversight of Canadian mining projects near multiple transboundary rivers that originate in B.C.