Iran has no plans to develop nuclear weapons, Russian President Vladimir Putin says.
Russia co-operates with Iran's nuclear programme
At a news conference in Moscow, Mr Putin said he had been given assurances by his Iranian counterpart Mohammad Khatami in a telephone conversation two days ago.
The International Atomic Energy Agency (IAEA) - the United Nations nuclear watchdog - has called on Iran to allow stricter inspections of its nuclear facilities.
US President George W Bush urged the world on Thursday to warn Tehran against developing nuclear weapons.
Russia is helping Iran to build an $800m nuclear reactor in the south-western port of Bushehr.
'Ready to sign'
President Khatami's telephone call to the Russian leader was made as the IAEA was meeting in Vienna to demand that Tehran sign an additional protocol to the Nuclear Non-Proliferation Treaty (NPT) "as soon as possible and without conditions".
"The Iranian leadership is ready to fully meet all the IAEA's demands regarding control over its nuclear programme," Mr Putin told journalists.
The IAEA urged Iran to be transparent about its nuclear objectives, in order to reassure the world it was not developing nuclear weapons.
The additional protocol to the NPT would allow for more intensive and short-notice inspections of Iranian nuclear facilities.
IAEA inspection teams are due to return to Iran shortly.