"For the United States, the threat posed by Iran is not direct, in other words they do not at the current level of development have the capacity to launch a nuclear war-headed missile that could strike the United States," Bolton told reporters in Bahrain.

"But they can strike our friends and allies in the region and the broader region here," he said.

Bolton, a noted hawk in President George W. Bush's administration, reaffirmed Washington's belief that Iran "has been pursuing this strategic decision to acquire nuclear weapons and ballistic missiles delivery systems."

Tehran insists that its nuclear programme is purely of civilian nature.

The US official, on a tour of the Gulf, said that the issue at stake was whether Iran creates "a new strategic reality in the region and around the world, and whether we will be able to stop it in advance.

"We would like to see a peaceful and diplomatic solution to the Iranian efforts," he said.

Bolton's comments come amid a hardening of US rhetoric against the Islamic republic, which Bush has already lumped into an "axis of evil".

Earlier this month, Bush said he could not rule out using force if Tehran failed to rein in its nuclear plans, and US Vice President Dick Cheney said Iran was "right at the top of the list" of global trouble spots.

Cheney also warned that Israel might launch a pre-emptive strike on its own to shut down Iran's nuclear programme.

All rights reserved. � 2005 Agence France-Presse. Sections of the information displayed on this page (dispatches, photographs, logos) are protected by intellectual property rights owned by Agence France-Presse. As a consequence, you may not copy, reproduce, modify, transmit, publish, display or in any way commercially exploit any of the content of this section without the prior written consent of Agence France-Presse.