UN atomic watchdog chief Mohamed ElBaradei said Monday that the disputed deal reached last month between Iran and International Atomic Energy Agency (IAEA) is a right step forward to resolve Iran's nuclear crisis.
The agreement is "an important step in the right direction," ElBaradei told a meeting of IAEA governing board that opened Monday in Vienna.
Iran has pledged late last month to answer outstanding questions about its controversial nuclear program, which some western countries, including the United States, only considered as Iran's fresh trick to delay UN sanctions.
To address the global mistrust, Iran need to demonstrate transparency for its nuclear program beyond the limited UN plan, ElBaradei said.
It was "indispensable" for Iran to allow wider-ranging inspections and suspend enrichment-related activities demanded by the IAEA and U.N. Security Council resolutions, he said.
"Resolving all outstanding issues in the next two to three months, after a long deadlock, would go a long way towards building the confidence of the international community in the peaceful nature of Iran's past nuclear program," he said.
Meanwhile, the UN nuclear chief called for more patience from some skeptical countries on Iran at the meeting of the 35-nation governors which is highlighted by a fierce debate on Iran.
The United States has recently softened its defiance and reiterated its diplomatic stand on Iran.
US Ambassador Gregory Schulte welcomed the work plan as a 'potentially important process' if Iran could fully cooperate.
Still, "we will press for rapid cooperation (by Iran) rather than continued delay and many countries will be joining us in doing so," he said.
Iran's top nuclear negotiator Ali Larijani said Sunday it was "impossible" that Tehran would suspend uranium enrichment, which Iran repeatedly claims will only be used for peaceful means such as generating power.
Western countries has been pushing for UN sanctions to stop Iran's nuclear program, which could be used to make nuclear weapons.