"Iran is favourable toward negotiations that are just, logical and without preconditions, but refuses the language of force," Ahmad Khatami said in a sermon broadcast on state radio today.
"Using the language of force with Iran is a foolish and clumsy attitude," said Ahmad Khatami, who is a member of Iran's Assembly of Experts.
Iran said it would soon announce latest successes in its quest for nuclear power that the West claims is a guise for acquiring atomic weapons.
The US and other world powers have reacted coolly to Iran's response to an incentives package offered by the five permanent security council members and Germany in return for a moratorium on sensitive uranium activities.
"During the war in Lebanon, the security council showed that it acted as the United States' valet... We advise Russia and China not to fall into the Americans' trap," he said.
Iranian government spokesman Gholamhossein Elham also announced Iran would soon unveil some new achievements in its nuclear program.
"In the nuclear domain, we have made progress and obtained new scientific successes which will be announced soon," government spokesman Gholamhossein Elham said during Friday prayers.
He did not elaborate.
Iran said on Wednesday it would soon announce an atomic breakthrough.
"The announcement will highlight Iran's mastery of different areas in nuclear science and will reinforce Iran's position as a nuclear country," a source told lranian local media.
Russian Defence Minister Sergei Ivanov said sanctions against Iran after its response to the world powers' demand to freeze uranium enrichment and reprocessing activities was as yet "premature".
Iran is suspected by the West of trying to build nuclear weapons under cover of a civilian nuclear power program.
Teheran has consistently rejected this suspicion and has insisted it has the right to its own nuclear power program.
France meanwhile said "technical contacts" could take place with Iran in the coming days to clarify some aspects of its response to the international offer.
"It is a possibility in the coming days, if we believe it is seen as useful on both sides. There could be technical contacts to clarify certain aspects of the dossier sent by the Iranians," foreign ministry spokesman Jean-Baptiste Mattei said.
French President Jacques Chirac said earlier that he and German Chancellor Angela Merkel agreed Teheran's response was "ambiguous".
British ambassador to the UN Emyr Jones Parry went further, describing Iran's response as "inadequate" and "short" of security council requirements.
"Our capitals are working on our response to the inadequate response we've received from Iran," he told reporters.
"We need to give a measured consideration to what has been sent to us by Iran, but quite clearly something which is short of what the council is looking for."
World oil prices rose on the persistent standoff.
In London, benchmark Brent North Sea crude for October delivery climbed US60 cents to $US73.28 dollars per barrel in electronic deals.
New York's main contract, light sweet crude for delivery in October, rose US69 cents to $US73.05 per barrel in pit trading.