"We will not sit [with arms folded] to wait for what others will do to us," Mr Shamkhani told Al Jazeera television when asked if Iran would respond to an American attack on its nuclear facilities.
"Some military commanders in Iran are convinced that preventive operations which the Americans talk about are not their monopoly.
"America is not the only one present in the region. We are also present, from Khost to Kandahar in Afghanistan; we are present in the Gulf and we can be present in Iraq.
"The US military presence [in Iraq] will not become an element of strength [for Washington] at our expense. The opposite is true, because their forces would turn into a hostage" in Iranian hands in the event of an attack, he said.
Mr Shamkhani, who was asked about the possibility of an American or Israeli strike against Iran's atomic power plant in Bushehr, said: "We will consider any strike against our nuclear installations as an attack on Iran as a whole, and we will retaliate with all our strength.
"Where Israel is concerned, we have no doubt that it is an evil entity and it will not be able to launch any military operation without an American green light. You cannot separate the two."
Earlier, a commander of Iran's elite Revolutionary Guards was quoted in the Iranian press as saying that the Iranian Government would strike the Israeli reactor at Dimona if Israel attacks the Islamic republic's own burgeoning nuclear facilities.
"If Israel fires one missile at Bushehr atomic power plant, it should permanently forget about Dimona nuclear centre, where it produces and keeps its nuclear weapons and Israel would be responsible for the terrifying consequence of this move," General Mohammad Baqer Zolqadr warned.
Iran's controversial bid to generate nuclear power at its plant being built at Bushehr is seen by arch-enemies Israel and the United States as a cover for nuclear weapons development.
The latest comments mark an escalation in an exchange of threats between Israel and Iran in recent weeks, leading to speculation that there may be a repeat of Israel's strike against Iraqi nuclear facilities at Osirak in 1981.
Iran insists that its nuclear intentions are peaceful, while pointing at its enemy's alleged nuclear arsenal, which Israel neither confirms nor denies possessing.
By No War 19 August 04
