“There is an understanding that such a visit could take place after the current session of the [IAEA] Board of Governors,” he said.

Iran has twice sent letters to the IAEA inviting experts to visit its nuclear facilities, Ryabkov said.

Moscow hopes that the Iran Six, including Russia, the United States, China, Britain, France and Germany, will meet with Iranian officials before the end of the year, he said.

The Iran Six has been trying since 2003 to convince Tehran to halt its uranium enrichment program.

Western powers and Israel suspect Iran of seeking to build nuclear weapons. Iran denies this, saying its program is of a civilian nature. Speculation has been building that Israel is considering a preemptive strike on Iran's nuclear facilities.

Russia has recently proposed a strategy for restoring trust in Iran’s nuclear program, which the Islamic Republic says is designed to generate civilian energy.

On Thursday, IAEA chief Yukiya Amano said the information contained in the Agency’s latest report on the military dimension of Iran's nuclear program is credible.

Amano said his report identified in detail the issues which Iran needs to address in order to restore international confidence in what it says is the exclusively peaceful nature of its nuclear program.

The IAEA continues to verify the non-diversion of nuclear material declared by Iran under its Safeguards Agreement, Amano said.

"But, as Iran is not providing the necessary cooperation, including by not implementing its Additional Protocol, the Agency is unable to provide credible assurance about the absence of undeclared nuclear material and activities in Iran, and therefore to conclude that all nuclear material in Iran is in peaceful activities," he said.