The next round of nuclear talks between Iran and the six world powers will be held in Istanbul April 14, a spokesman for the EU foreign policy chief Catherine Ashton confirmed Sunday, DPA reported.
Both sides had initially agreed on Istanbul, which also hosted the talks in January last year, as venue for the talks, but Iran said earlier this week that it would prefer Baghdad or Beijing over Istanbul.
Earlier Sunday the website of the Iranian news network Press TV had quoted unnamed Iranian officials as saying that Istanbul has been confirmed as the venue for the nuclear talks between the six world powers - Britain, China, France, Germany, Russia and the United States - and Iran.
Observers believe that the hesitation on Istanbul could be linked to differences with Turkey on the crisis in Syria. Iran is an ally of President Bashar al-Assad, while Turkey has called on al-Assad to step down and has condemned his deadly crackdown on opposition rebels.
The New York Times reported that the United States and other Western states would demand Iran close down its new enrichment site Fordo south of Tehran.
Another demand would be halting uranium enrichment at 20 per cent - which Iran uses for a medical reactor in Tehran - and exporting the estimated 100 kilograms of already produced 20-per-cent-enriched uranium.
"These demands are not rational," Iran's Atomic chief Fereydoon Abbasi told ISNA news agency.
Also on Sunday, President Mahmoud Ahmadinejad vowed that Iran would not withdraw from its nuclear course even in case of more sanctions and military threats against its nuclear sites.
"Iran does not want any problems and confrontation with anyone but the country would decisively continue this (nuclear) path," ISNA quoted the president as saying.
"Even if the whole world stood against Iran, still Iran would continue this path with nobody capable to stop it," Ahmadinejad added.
In a meeting Sunday in Tehran with visiting former Japanese premier Yukio Hatoyama, Ahmadinejad once again reiterated that Iran was not making nuclear weapons.
"Iran is principally against atomic bombs and any other weapons of mass destruction," Ahmadinejad told Hatoyama.
Earlier Sunday, Israel reiterated its stance on Tehran's disputed nuclear programme was unchanged. Defence Minister Ehud Barak said Israel's five demands remained in place, and that the minister had reiterated this position to "the most senior American officials."
Israel regards Iran as its prime existential threat, because of Tehran's nuclear programme, coupled with repeated statements by President Ahmadinejad and other Iranian leaders to wipe the Jewish state off the map.
Speculation has been growing in recent months that Israel intends to launch a military strike at Iran's nuclear facilities to end, or at least retard significantly, Iran's drive toward atomic weapons.
Israel's five requirements are: halting uranium enrichment to 20 per cent, removing all uranium enriched to this level to a third country; removing all uranium enriched to 3.5 per cent, except for several hundreds kilogrammes-worth; decommissioning the underground facility at Qom; placing all Iranian nuclear activity under IAEA supervision; revealing the full history and actions connection to "suspicious military plans."
In return, the statement said, Iran could receive fuel rods for its research reactor.