Officials from the United States, Britain, China, France, Russia and Germany convene on Wednesday in Shanghai, China, to discuss a plan to restart talks on Iran's nuclear issue, but Tehran's latest defiant moves indicate their job would not be easy.

On Monday, just two days before the key meeting, Iranian President Mahmoud Ahmadinejad said other nations can gain access to Iran's nuclear technology within the framework of International Atomic Energy Agency (IAEA) regulations.

"Experiences and valuable achievements of Iran concerning peaceful nuclear technology are reachable by other nations within the framework of IAEA regulations," Ahmadinejad said at a meeting with Philippine Foreign Affairs Secretary Alberto Romulo.

Monopolizing powers "are endeavoring to prevent nations from gaining access to the peaceful nuclear energy," he said.

But the Islamic Republic of Iran will resist this pressure and intends "to restore this right of acquiring nuclear technology for peaceful purposes to all nations," Ahmadinejad added.

The Iranian president's remarks came one day after Gholamreza Aghazadeh, the head of Iran's Atomic Energy Organization, abruptly canceled a meeting with IAEA chief Mohamed ElBaradei.

The meeting to discuss Tehran's nuclear program was due to have taken place in Vienna Monday but has now been put off to a more "appropriate time," Iran's official IRNA news agency reported.

An IAEA official later confirmed the report, saying no reason had been given for the cancellation.

According to a senior diplomat in Vienna, ElBaradei had planned to use the meeting to renew a request for more information on allegations that Tehran had tried to make nuclear weapons.

The meeting would have also focused on Iran's latest show of defiance toward UN Security Council demands to suspend uranium enrichment, the diplomat said.