U.S. lawmakers want their counterparts in the European Parliament to back away from a resolution that would split up Google by separating search engines from other online services.

Thirteen U.S. lawmakers raised concerns about the resolution, which calls for search engines to be unbundled from online services, in two letters sent to Parliament leaders on Tuesday. The European Parliament may vote Thursday on the resolution calling on the European Commission to separate search engines from other commercial services as one way to solve competition complaints about Google.

The resolution doesn’t mention Google specifically, but “it is a search engine that would be impacted,” said a spokesman for Representative Anna Eshoo, a California Democrat who organized one of the letters.

The resolution would “deter continued innovation and investment from U.S.-based Internet companies,” 12 U.S. lawmakers said in one of the letters. The proposal could slow cross-border data traffic “at the expense of millions of people across Europe who enjoy the use of these online services every day,” said the letter, signed by Eshoo, Zoe Lofgren and Mike Honda, all California Democrats, Jared Polis, a Colorado Democrat, Jason Chaffetz, a Utah Republican, and Darrell Issa, a California Republican.

U.S. firms have invested trillions of dollars in the E.U., the letter said. “We support healthy competition and a level playing field for Internet companies in the U.S. and around the globe, and we believe these goals can be accomplished through the traditional regulatory process,” the letter continued.

The European Parliament doesn’t have the power to split up Google, but the European Commission, its executive arm, could take that action to resolve antitrust complaints.

Separate from the first letter, Representative Bob Goodlatte, a Virginia Republican and chairman of the House Judiciary Committee, also voiced opposition to the European proposal in a letter to lawmakers there.

U.S. lawmakers were “troubled to learn that some European elected representatives are encouraging antitrust enforcement efforts that appear to be motivated by politics, rather than grounded in factual and legal principles,” Goodlatte wrote. “We believe that antitrust enforcement should be applied independent of politics and firmly rooted in our shared international principles.

“Policies that run counter these principles undermine our free markets and ultimately harm both our businesses and our consumers,” he added.