The International Atomic Energy Agency (IAEA) will need additional funds to carry out the more intensive inspection regime under the deal between Iran and six world powers, IAEA chief Yukiya Amano said Thursday in Vienna, dpa reported.
The landmark deal that was signed Sunday in Geneva obliges Iran to allow more frequent inspections, grant access to additional locations, and to place limitations on its nuclear activities.
In return, Britain, China, France, Russia, the United States and Germany have pledged to suspend some sanctions.
The IAEA was now in the process of determining its exact tasks under the agreement, Amano said.
"Naturally, this requires a significant amount of money and manpower," he said. "I do not think we can cover everything by our own budget."
Iran told the IAEA Thursday that it would take the first step towards opening its nuclear programme to closer scrutiny on December 8, Amano said.
On that day, IAEA inspectors will be allowed to visit a previously off-limits plant that makes coolant for the Arak reactor, he told the nuclear agency's governing board.
The visit is part of an agreement between Tehran and the IAEA that was signed earlier this month.
This agreement and the Geneva deal marked the first time that Tehran's leaders make significant nuclear concessions in the 10 years since the country's nuclear programme came to light.
Under the Geneva deal, Tehran agreed to stop construction of the Arak reactor, and to curb its uranium enrichment programme.
Arak has raised concerns because this research reactor would produce plutonium that could be used in weapons, while the enriched uranium could also be processed further and turned into warheads.
Once the Geneva agreement starts being implemented, likely early next year, it would oblige both sides for six months. During that period, the six powers and Iran want to negotiate a wider-reaching agreement that would ask Tehran for further nuclear concessions but would eventually result in a complete lifting of sanctions.