WASHINGTON (AP) – The Bush administration moved Friday to financially clamp down on four Iranian companies suspected of connections to Tehran’s nuclear program.

It marked the government’s latest move to put the financial squeeze on Iran, a country that America accuses of fostering terrorism and whose nuclear ambitions have drawn international rebuke.

The Treasury Department’s action is against Pars Tarash, Farayand Technique, Fajr Industries Group and Mizan Machine Manufacturing Group.

The action means that any bank accounts or other financial assets belonging to these three companies found in the United States must be frozen. Americans also are forbidden from doing business with them.

“So long as Iran continues to pursue a nuclear program in defiance of the international community’s calls to halt enrichment, we will continue to hold those responsible to account for their conduct,” said Stuart Levey, the department’s undersecretary for terrorism and financial intelligence.

The action comes as leaders of the world’s eight major industrial powers, meeting in Heiligendamm, Germany, on Friday, sent a warning to Iran over its disputed nuclear program.

The group said it would support “adopting further measures” if Iran fails to suspend enriching uranium, which can produce fuel for civilian energy or material for a bomb. The statement was a sign of support for U.N. Security Council moves to discuss a third set of sanctions against Iran.

The Treasury Department alleges that Pars Tarash and Farayand Technique are owned or controlled or act on behalf of the Atomic Energy Organization of Iran or its subsidiary, the Kalaye Electric Co.

The Atomic Energy Organization of Iran, or AEOI, manages Iran’s overall nuclear program and reports directly to Iran’s president, the department said. It is Iran’s main research and development facility for nuclear technology, the department said.

The department alleges that Fajr Industries and Mizan Machine are owned or controlled or acting on behalf of Iran’s Aerospace Industries Organization. That group is a subsidiary of Iran’s defense ministry and is the overall manager and coordinator of Iran’s missile program, Treasury said.