Iranian President Mahmoud Ahmadinejad has dismissed a possible European offer of incentives to induce Iran to suspend its nuclear enrichment programme.
Ahmadinejad says he will not accept nuclear suspension again
He likened the incentives, which European negotiators are said to be considering, to the offer of "walnuts and chocolates" in exchange for gold.
France, Germany and the UK are thought to be discussing plans to offer Iran a light-water reactor.
Iran denies accusations among Western powers that it is seeking nuclear arms.
France, Germany and the UK had been due to meet the US, Russia and China on Friday, but this has been delayed.
A spokesman for the foreign office in London said this was to allow for more detailed discussion of the offer.
The meeting is now expected to be held in the next 10 days.
Meanwhile Iranian Foreign Ministry spokesman Hamid Reza Asefi said his government would offer its own economic incentives to Europe to recognise its right to enrich uranium.
"Iran's 70-million population market is a good incentive for Europe," he was quoted as saying by local media.
The BBC's Frances Harrison in Tehran says Mr Asefi's remarks made fun of the Europeans' intense diplomatic efforts.
And speaking to supporters in the central Iranian city of Arak, Mr Ahmadinejad said the Europeans were treating Iran like a child:
"They say they want to give us incentives! Do you think you are dealing with a four-year-old child to whom you can give some walnuts and chocolates and get gold from him?"
Mr Ahmadinejad said Iran simply would not accept suspension of its nuclear work again, having agreed to it for two years and found it was a "bitter experience".
And he warned that the West should not force governments who have signed the nuclear Non-Proliferation Treaty (NPT) to pull out of it.
On Tuesday, the three EU states were reported to be considering reviving an offer to Iran of a light-water nuclear reactor as part of a package to persuade it to suspend nuclear fuel enrichment and research and avoid possible UN Security Council sanctions.
A reactor was tentatively offered in a previous European package of incentives in August that was swiftly rejected by Iran, says the BBC's Frances Harrison in Tehran.
The EU's latest reported initiative comes as the US and some European governments seek a tough resolution on Iran at the UN Security Council.
China and Russia - both veto-holding members of the Security Council - do not want to support any resolution that might eventually lead to further resolutions threatening sanctions or military action.
In Tehran, many suspect the latest package of European incentives is aimed more at wooing Russian and Chinese support than really striking a deal with Iran, our correspondent says.