The head of the UN nuclear watchdog said today Iran must be more forthcoming with inspectors examining its nuclear programme.
Mr Mohamed El Baradei was speaking as the board of governors of his International Atomic Energy Agency (IAEA) met one day after Iran's nuclear planners scored a major victory with a key uranium fuel supply deal with Russia.
"In view of the past undeclared nature of significant aspects of Iran's nuclear programme, a confidence deficit has been created and it is therefore essential that Iran works closely with the agency in a proactive manner," Mr El Baradei said in a speech to the IAEA board.
"In some cases, the receipt of information is still pending, which in turn delays our work," he said.
The United States claims Iran's nuclear programme is a front for developing an atomic bomb.
Mr El Baradei told reporters he welcomed an Iranian decision to show the IAEA a 1987 offer from aides to Pakistan's top nuclear scientist and atomic black marketeer, Abdul Qadeer Khan, to supply nuclear equipment.
He said the written offer was for centrifuges used to produce enriched-uranium fuel, a revelation that several Western board members said deepened their suspicions about Iran's programme.
"They indicated that they did not take these people up on the entirety of the offer," Mr El Baradei said.
Iran, OPEC's second largest oil producer, says its nuclear intentions are limited to peaceful generation of electricity.
Mr El Baradei said the agency had been able to verify Tehran's suspension of activities connected with uranium enrichment, a process of purifying uranium for use as fuel for nuclear power plants or, when very highly enriched, in weapons.