By Frances Harrison
BBC News, Teheran
Iran's foreign ministry spokesman has warned Tehran will not hesitate to retaliate with a crushing blow if Israel attacks its nuclear sites.
Iran wants to have 3,000 centrifuge machines operational by March
This follows comments by Israel's deputy defence minister Ephraim Sneh.
He had suggested Israel could launch military strikes against Iranian nuclear installations as a last resort.
Mohammed Ali Hosseini said if Israel indulged in such stupidity, then the response of Iranian fighters would be emphatic, crushing and immediate.
Mr Hosseini said it would not take one second.
Earlier, Mr Sneh had said he was not advocating a military attack, but considered it a last resort and he added sometimes the last resort was the only resort.
Also on the nuclear issue, Iran's Foreign Ministry reiterated the country's policy of trying to have 3,000 centrifuge machines operational by March next year in order to enrich uranium.
However so far, all the indications are that Iran only has a couple of hundred centrifuges working.
'Conciliatory' on US talks
But on the issue of direct talks with the United States over Iraq, Iran's foreign ministry has struck a more conciliatory note.
Mr Hosseini repeated that if there was a written official request from the US for talks on regional issues, then Tehran would consider it.
Mr Hosseini also mentioned the task force headed by former US secretary of state James Baker, which is currently examining the option of talks with Iran and Syria to try and improve the security situation inside Iraq.