Sen. Ted Cruz (R-TX) told a town hall Sunday evening that U.S. states should continue their Iran sanctions–and impose new ones–to stop the Iranian regime from obtaining a nuclear weapon.

“I think that states should act and lead to do exactly that,” he said, speaking before a crowd of 750 near Birmingham, as reported by Roll Call.

Cruz cited the constitutional precedent set by his own litigation before the Supreme Court in Medellin v. Texas (2008), in which the Court held that international treaties do not trump state law unless accompanied by enabling federal legislation.

“[W]e ought to do everything we can to resist this … Iranian deal,” Cruz said, calling on the states to lead.

Both New York and California intend to retain their sanctions on Iran, according to legislators who spoke with Breitbart News. New York in particular maintains a blacklist of companies and individuals that are prevented from contracting with the State of New York.

The Iran deal requires the U.S. government to urge states to drop sanctions, but Secretary of State John Kerry admitted in recent testimony before the House Foreign Affairs Committee that states can continue their sanctions.

Constitutional lawyers David B. Rivkin and Lee A. Casey also argued in an op-ed in the Wall Street Journal that states can–and should–resist the Iran deal through applying their own sanctions.