TEHRAN -- UN nuclear agency chief Mohammed ElBaradei said on Saturday he was confident Iran would recognize it was in its best interest to work with the United Nations on making clear its nuclear aims.

"The more cooperative they are, the more transparent they are, the more confidence they can create in the international community and the quicker we can resolve the whole nuclear issue in Iran," ElBaradei, the director of the International Atomic Energy Agency, told Reuters on the sidelines of an economic meeting in Jordan. Asked about remarks by the head of Iran's atomic energy program, Gholamreza Aghazadeh, earlier on Saturday, who said Iran was ready to cooperate more actively with the IAEA on its nuclear program, ElBaradei said, "I would welcome that."

"I read a statement by Aghazadeh yesterday saying Iran will not allow environmental sampling. I think that would have been very unhelpful.

"I have lots of confidence that Iran will understand that it is in its best interest to work with the International Atomic Energy Agency," he said.

Iran has faced mounting pressure in recent weeks from the IAEA and the United States over the nature of its nuclear program.

It urged Iran to remain "transparent" and accept without delay or conditions more intrusive, short-notice inspections.

Washington believes Iran is secretly seeking to develop an atomic weapons program and on Friday warned that the United States reserved the right to use military action to stop Tehran making such weapons. Iran insists its nuclear program is designed to produce electricity.

Meanwhile, the UN nuclear watchdog's failure to condemn Iran has reinforced Russia's willingness to help the Islamic republic build up its nuclear program, the Russian Foreign Ministry said Saturday.

The IAEA noted in a report presented at a Vienna meeting last Wednesday that Iran had failed to report certain nuclear activities. Yet it stopped short of slapping sanctions on the country and merely called for it to accept stricter inspections of its nuclear sites.

"Since the IAEA issued no reproach, there is no reason to put an end to our cooperation," Russian Foreign Ministry Spokesman Alexander Yakovenko told AFP.

Russia has drawn U.S. ire for building Iran's first nuclear reactor at Bushehr and for insisting that the oil-rich country is not seeking to develop a nuclear weapons program.

"We are for total transparency of Iran's nuclear programs and we are for Iran's signing the additional protocol to allay the concerns expressed by certain countries," he said. The chairman of the Russian Duma's Committee for CIS Affairs, Andrei Kokoshin, also said on Friday that Tehran-Moscow nuclear cooperation is "transparent."

During a meeting with Iranian Ambassador to Moscow Gholamreza Shafei, he said the pursuit of transparent nuclear cooperation is a legitimate right of both states.

"Moscow believes that Tehran has the right to pursue nuclear activities," he said.

As a signatory to the nuclear Non-Proliferation Treaty (NPT), Iran has the right to insist that it be allowed to construct the necessary facilities in this regard, Kokoshin added.

He said that the Islamic Republic of Iran enjoys special importance in Russian foreign policy and called for further expansion of ties between the two countries.

Referring to the friendly cooperation between Tehran and Moscow and their similar stances on various regional and international issues, including those affecting Afghanistan and Tajikistan, he stated that the two countries' cooperation is in line with the need to advance their national interests.

Moscow respects Tehran's fair and principled stances on various issues, he added.

For his part, Shafei voiced the determination of senior Iranian officials to expand ties with Russia and praised Russia's determination to stand by Iran despite the fact that the U.S. is pressuring Russia to end its nuclear cooperation with Iran.

The Islamic Republic of Iran is pursuing a nuclear program for peaceful purposes as guaranteed by international laws and regulations, the Iranian envoy said.

An agreement between Russia and Iran on the return of spent fuel from the nuclear power plant under construction in Bushehr may be signed in the near future, Russian Atomic Energy Minister Alexander Rumyantsev told reporters, according to Itar-Tass.

All parties concerned have formulated a draft agreement, but it still must be scrutinized by independent ecological specialists.

The first reactor at the Bushehr Nuclear Power Plant is scheduled to become operational in 2004. The power plant will go on stream in 2005.

The slight delay in the schedule is due to industrial reasons and is in no way related to the political situation, Rumyantsev said.

Russia will begin supplying Iran nuclear fuel after Iran signs the Additional Protocol to the nuclear Non-Proliferation Treaty, allowing greater inspection of its nuclear facilities by the IAEA.