The French foreign minister Bernard Kouchner said on French television and radio "We have to prepare for the worst, and the worst is war." He also said France wanted the European Union to back new sanctions against Iran, outside the of the UN Security Council, to pressure Tehran to give up its nuclear ambitions.

The Iranian president, Mahmoud Ahmadinejad, says that Iran need nuclear technology to produce electricity.

"Of course we will not step back," he said.

"We have mastered the technology to enrich uranium and we have arrived at an industrial stage. The West are talking about imposing sanctions on us. But they cannot do this," he said.

Al Jazeera