Four Republican state attorneys general are suing to stop the Obama administration from transferring oversight of the internet to an international body, arguing the transition would violate the U.S. Constitution.

The lawsuit — filed Wednesday in a Texas federal court — threatens to throw up a new roadblock to one of the White House’s top tech priorities, just days before the scheduled Oct. 1 transfer of the internet’s address system is set to take place.

In their lawsuit, the attorneys general for Arizona, Oklahoma, Nevada and Texas contend that the transition, lacking congressional approval, amounts to an illegal giveaway of U.S. government property. They also express fear that the proposed new steward of the system, a nonprofit known as ICANN, would be so unchecked that it could “effectively enable or prohibit speech on the Internet.”

The four states further contend that ICANN could revoke the U.S. government’s exclusive use of .gov and .mil, the domains used by states, federal agencies and the U.S. military for their websites. And the four attorneys general argue that ICANN’s “current practices often foster a lack of transparency that, in turn, allows illegal activity to occur.”

“Trusting authoritarian regimes to ensure the continued freedom of the internet is lunacy,” said Texas Attorney General Ken Paxton in a statement. “The president does not have the authority to simply give away America’s pioneering role in ensuring that the internet remains a place where free expression can flourish.”

A spokeswoman for NTIA, the Commerce Department agency handling the transition, declined to comment on the case Thursday. Previously, federal officials have said any delay to their transition plans would embolden the U.S. government’s harshest critics, Politico reports.