Tehran - Tehran said that the delay of the nuclear fuel deal has economic and not political reasons, ISNA news agency reported Monday.

"The nuclear deal has some economic angles and therefore technical and economic experts' opinions should be thoroughly considered [before finalizing the deal]," Iran's chief nuclear negotiator Saeid Jalili told visiting Russian Deputy Foreign Minister Sergei Ryabkov.

The deal, which was proposed in talks with France, Russia and the United States, requires Iran to ship its low-enriched uranium abroad for further processing into fuel to be used in a medical-purpose nuclear reactor in Tehran under constant monitoring by the International Atomic Energy Agency (IAEA).

Despite remarks by Iranian lawmakers over Iran having rejected the deal, the relevant officials have not yet given a clear and final reply and have asked for more talks to clarify technical and economic details.

"We would welcome further talks with the world powers," Jalili said.

Following the October 1 meeting in Geneva, Iran and the five permanent members of the United Nations Security Council - Britain, China, France, Russia and the United States - plus Germany were supposed to resume talks at the end of October.

The talks, however, had to be postponed after Iran could give no clear reply on the nuclear fuel deal which the IAEA and the world powers regard as a first step to breaking the deadlock over Tehran's nuclear programmes.

Iran is supposed to swap 3.5-per-cent-enriched uranium from the Natanz plant in central Iran for 20-per-cent material from Russia and France to be used for the Tehran reactor.

Iran has reportedly agreed in principle but wants some changes such as the option of exchanging its 1.2 tons of uranium in several phases or purchasing a portion of the high-enriched uranium, rather than exchanging its stock in one go.

Some technical experts in Tehran believe that purchasing the fuel for the Tehran reactor would be more economical for Iran than exchanging the low-enriched uranium for whose know-how and production Iran has invested a lot.

Some observers have suggested that Iran is using the nuclear fuel talks as pretext for resuming talks with the world powers over the acknowledgement of its nuclear programmes. (dpa)