WASHINGTON, Oct 25: The Bush administration on Thursday announced an unprecedented package of unilateral sanctions against Iran, designating the Iranian Revolutionary Guard Corps a proliferator of weapons of mass destruction and the elite Quds Force a supporter of terrorism.

The sanctions could also affect the proposed Iran-Pakistan-India gas pipeline as in 2006 the Iranian government awarded a $1.3 billion contract to the Guards to build the pipeline up to Pakistan’s border.

A US law already forbids investment in Iranian oil and gas projects and the latest sanctions will further increase pressure on Pakistan to shelve the project. “(We) are announcing several new steps to increase the costs to Iran of its irresponsible behaviour,” said US Secretary of State Condoleezza Rice while announcing the sanctions at a joint briefing with Secretary of the Treasury Henry M. Paulson.

“Because of the Revolutionary Guard’s support for proliferation and because of the Quds Force support for terrorism … the United States today is designating both of these groups,” she said.

The Revolutionary Guard “is so deeply entrenched in Iran’s economy, that it is increasingly likely that if you are doing business with Iran you are doing business with the IRGC,” said Secretary Paulson.

Ms Rice said the US was also designating three Iranian state-owned banks: Bank Melli and Mellat, for their involvement in proliferation activities, and Bank Saderat as a terrorist financier.

Several other Iranian individuals and organisations have been sanctioned. These include five Revolutionary Guard leaders, nine businesses and the Iranian Ministry of Defence and Armed Forces Logistics.

The sanctions mark the first time that the United States has tried to isolate or punish another country’s military. It is the broadest set of punitive measures imposed on Iran since the 1979 takeover of the US Embassy, and includes a call for other countries and firms to stop doing business with three major Iranian banks.

The move caps a year of growing US pressure on Iran, including billions of dollars in arms sales to Persian Gulf states and Israel, interception of Iranian arms shipments in Iraq and Afghanistan, detention of Iranian agents in Iraq, and pressure on the UN and European allies to increase Iran’s isolation.