Kouchner said Sunday his country must prepare for the possibility of war against Iran over its nuclear program.
The French minister also told RTL radio and LCI television that the world's major powers should use further sanctions against Iran.
Kouchner said France had asked French firms not to bid for tenders in the Islamic Republic.
The Israeli occupying regime was quick to welcome the acerbic remarks by Kouchner, describing them as "positive".
The Zionist regime is the Middle East's sole nuclear power, which is believed to possess more than 200 atomic warheads.
In an editorial, Iran's IRNA news agency said, "The new occupants of the Elysee want to copy the White House," referring to the French presidential palace.
It said that since Nicolas Sarkozy took over as president from Jacques Chirac and promoted closer ties with the US, "he has taken on an American skin".
"The French people will never forget the era when a non-European moved into the Elysee," it said.
Sarkozy has himself bluntly warned that Iran risks being bombed if the nuclear standoff is not resolved
In Sunday's interview, Kouchner said, "We have to prepare for the worst, and the worst is war."
IRNA added: "The occupants of the Elysee have become the executors of the will of the White House and have adopted a tone that is even harder, even more inflammatory and more illogical than that of Washington."
France has economic interests in Iran, especially in the oil and automobile industries, but its line on the nuclear standoff has hardened considerably since Sarkozy came to power.
Iran has said it will never initiate any attack but will respond with crushing force if any strike is launched on its territory.
A top general in the Revolutionary Guards said that Iran's missiles could hit a range of targets belonging to US troops operating in neighboring Iraq and Afghanistan.
"Today the Americans are around our country but this does not mean that they are encircling us. They are encircled themselves and are within our range," General Mohammad Hassan Koussechi told IRNA.
"If the United States is saying that they have identified 2,000 targets in Iran, then what is certain is that it is the Americans who are all around Iran and are equally our targets."
(Note: this is the third time that a senior Pasdaran commander openly threatens to retaliate against US forces in the Middle East. Before General Mohammad Hassan Koussechi the same threat was previously made by Brigadier General Mohammad Ali Jaafari, the recently appointed commander of the Pasdaran, and by Major General Yahya Rahim Safavi, former commander of the Pasdaran and currently Senior Advisor to the Iranian Supreme Leader Ali Khamenei for Military Affairs. It is worth remembering here that the Pasdaran control Iranian missile forces and that they are directly subordinated to the Supreme Leader)
The chief UN nuclear inspector criticized talk of attacking Iran as hype Monday, invoking the war in Iraq and saying such options should only be considered as a last resort and only if authorized by the UN Security Council.
"I would not talk about any use of force," said Mohamed ElBaradei, the head of the International Atomic Energy Agency, in an indirect response to French warnings that the world had to be prepared for the possibility of war in the event that Iran obtains atomic weapons.
ElBaradei urged the world to remember Iraq before considering any similar
action against Tehran.
"There are rules on how to use force, and I would hope that everybody would have gotten the lesson after the Iraq situation, where 70,000 innocent civilians* have lost their lives on the suspicion that a country has nuclear weapons," ElBaradei told reporters.
He was alluding to a key U.S. argument for invading Iraq in 2003, that
Saddam Hussein had weapons of mass destruction, including nuclear arms.
Four years later, no such arsenals have been found.
ElBaradei, speaking outside a 144-nation meeting of his agency, urged both sides to back away from confrontation, in comments addressed both to Iran and the U.S.-led group of nations pressing for new U.N. sanctions on Tehran for its refusal to end uranium enrichment.
*El Baradei is wrong here. The actual figure of casualties after the US invasion of Iraq is already over one million (sldo see updated info box on the lower right of this page)