The new chief of the UN atomic watchdog, Yukiya Amano, accused Iran Monday of not cooperating sufficiently with an investigation into its contested nuclear activities.
In an opening address to an International Atomic Energy Agency board of governors meeting, Amano also said a UN-brokered deal to supply Iran with fuel for a nuclear research reactor was however still on table.
"The agency continues ... to verify the non-diversion of declared nuclear material in Iran, but we cannot confirm that all nuclear material in Iran is in peaceful activities because Iran has not provided the agency with the necessary cooperation," he said.
"The necessary cooperation includes, among other things, implementation of relevant resolutions of the IAEA board of governors and the United Nations Security Council," the Japanese diplomat said.
It also meant allowing IAEA inspectors to conduct snap inspections, notifying the agency of plans to build nuclear plants and "clarification of issues related to possible military dimensions to Iran?s nuclear programme."
Amano, who took over the the reins of the UN watchdog on December 1, circulated a report to IAEA member states 10 days ago, the wording of which was seen as blunter and tougher than that used by his predecessor Mohamed ElBaradei.
Amano expressed concern that Tehran may be "currently" working on a nuclear warhead and confirms that Iran has started enriching uranium to higher levels, theoretically bringing it close the levels needed for an atomic bomb.
But diplomats close to the IAEA said Amano felt too much attention had been placed on the comments.
On Sunday, Iran's supreme leader Ayatollah Ali Khamenei accused the IAEA of lacking independence and being "influenced by the United States."
The diplomats said the board of governors meet was unlikely to censure the Islamic republic over its contested nuclear work this time round, since the body passed just such a resolution against Iran in November.
Nevertheless, the meeting could pave the way for a new round of sanctions by the United Nations Security Council in New York, the diplomats said.
The Iran dossier has been at the UN Security Council since February 2006 and the council has slapped three rounds of sanctions on Tehran since then for refusing to halt its nuclear activities until the IAEA can verify they are exclusively peaceful as Iran claims.
The United States and its Western allies believe the Islamic republic is seeking to build an atomic bomb under the guise of its civilian nuclear programme, a charge Iran denies.
US Secretary of State Hillary Clinton said recently she hoped to see a UN Security Council resolution on new sanctions against Iran in the "next 30 to 60 days."
Of the five permanent members of the UN Security Council, Russia and China have both been reluctant to vote for sanctions in the past.
However, Moscow, which had enjoyed close ties with Tehran for many years, has shown growing irritation with Iran in recent months and now says it no longer excludes new sanctions.
Diplomats say that even so-called Non-Aligned countries on the IAEA board are growing increasingly frustrated at Iran's refusal to sign up to a nuclear fuel deal that would have helped appease fears about the nature of its atomic activities.
Iran insists it needs higher-enriched uranium to fuel a research reactor which makes radioisotopes for medical purposes, such as the treatment of cancer, where the current fuel is expected to run out by the end of this year.
The proposed deal would see Russia and France fashion the fuel out of Iran's own stockpile of low-enriched uranium, currently estimated to be just over 2,065 kilogrammes.
Amano said in his address however: "The arrangement proposed by the agency in October 2009 remains on the table."
"I believe it would ensure continued operation of the Tehran Research Reactor and serve as a confidence-building measure," he told the four-day meeting.

Copyright 2010 AFP Global Edition