Iran ruled out direct talks with Washington on Monday as Israel urged the world to take action against the Islamic republic's nuclear programme, warning it could destablise the Middle East.
US President George W. Bush, just into his second term of office, has warned Tehran not to develop nuclear weapons or risk possible military action, in an escalating round of tit-for-tat rhetoric between Iran and its archfoe.
"We have said before that if anyone wants to talks to us in a threatening language, we will adopt the same tone," Iranian government spokesman and cabinet secretary Abdollah Ramazanzadeh told reporters.
Last week, Bush -- who once lumped Iran in an "axis of evil" with Saddam Hussein's Iraq and North Korea -- said he could not rule out using force if Tehran failed to rein in its nuclear plans.
US Vice President Dick Cheney also warned that Israel might launch its own pre-emptive strike to end Iran's nuclear programme and he put Iran "right at the top of the list" of global trouble spots.
While Iran insists its nuclear activities are strictly for peaceful energy purposes, the European Union's "big three" -- Britain, France and Germany -- are engaged in a diplomatic effort aimed at securing long-term guarantees the clerical regime will not seek the bomb.
In an interview on Monday, Israel's Deputy Prime Minister Shimon Peres said: "The world must mobilise against the Iranian nuclear option."
"Iran has become the focal point of all the dangers of the Middle East... This problem should be of concern to the whole world and not just Israel," said Peres, the founder of Israel's nuclear programme.
Since the downfall of Saddam in 2003, Israel has come to regard the Islamic republic as its number one enemy.
Israel's chief spy Meir Dagan told the parliamentary foreign affairs and defence committee that Iran's nuclear ambitions were close to "the point of no return".
Iran, he said, was nearly able to manufacture enriched uranium without any external help, Israel's army radio quoted him as telling the committee.
"From there, the route to building a bomb is a short one, and so it is up to the international community to increase its efforts in order to prevent the arming of Tehran," Dagan said.
On Sunday, Iran warned any attack on its soil would be a "major strategic blunder" and has insisted that its nuclear activities are strictly peaceful.
"If they (the Americans) stop these threats and deal with us as equals and forget preconditions, we will think about the possibility of negotiating with this government," Ramazanzadeh said on Monday.
The New Yorker magazine reported that US commandos have been operating inside Iran since mid-2004, secretly scouting targets for possible air strikes targetting what the US says is a covert weapons programme.
Although Iran and the United States cut off direct diplomatic ties shortly after the 1979 Islamic revolution, Britain, France and Germany are working to secure long-term guarantees that Tehran will not manufacture an atomic bomb.
Iran has agreed to suspend sensitive nuclear fuel cycle work, which can be geared to both civil and military purposes, for the duration of the talks.
Israel itself has never publicly acknowledged having a nuclear arsenal but foreign experts believe it has produced between 100 and 200 nuclear warheads.