Iran needs stop button, says Rice

London: Western powers meet in London on Monday to discuss tightening UN sanctions on Iran amid tough talk between Washington and Iran over the Islamic Republic's nuclear programme.

President Mahmoud President Mahmoud Ahmadinejad declared on Sunday that Iran had "no brake and no reverse gear" on its plans, prompting US Secretary of State Condoleezza Rice to say Tehran needed a "stop button" for a programme the West fears is geared to producing nuclear arms.

US Vice President Dick Cheney said all options were on the table following Iran's refusal to adhere to a UN deadline for halting uranium enrichment. An Iranian deputy foreign minister responded by saying Iran was prepared even for war.

Cheney said during a visit to Australia that it would be a "serious mistake" to allow Iran to become a nuclear power.

British officials hosting Monday's talks of the five permanent United Nations Security Council members plus Germany say they are resolved to tackle the issue using diplomacy.

The London meeting is likely to discuss adding a travel ban on senior Iranian officials and restrictions on non-nuclear business to existing sanctions banning transfers of nuclear technology.

Washington has deployed a second aircraft carrier to the Gulf with supporting warships, a move widely seen as a warning to Iran.