Iran will continue to cooperate with the U.N. nuclear watchdog, Reuters reported.
The Foreign Ministry said on Monday, apparently confirming Tehran had given inspectors access to a reactor under construction after barring visits for a year.
The International Atomic Energy Agency is due to release a report on Iran's disputed nuclear program this week. Last week diplomats accredited to the Vienna-based agency said Iran had allowed the IAEA to inspect the Arak heavy water reactor site.
The U.N. agency had urged Iran to grant access so that it could verify that the site under construction was for peaceful uses only. The diplomats also said Iran had recently allowed an upgrade of monitoring at the Natanz uranium enrichment plant.
The changes were greeted with skepticism by the West, which suspects Iran is trying to build nuclear bombs. Tehran says its nuclear work is to generate electricity. Uranium enrichment can have both civilian and military uses.
"All our nuclear activities have been within the framework of the agency and the NPT (nuclear Non-Proliferation Treaty) ... (IAEA Director General Mohamed) ElBaradei has always confirmed Iran's cooperation with the agency," Foreign Ministry spokesman Hassan Qashqavi said.
"This trend will be continued in the future," he added, appearing to refer to the reported Arak visit.
The United States, Britain, France and Germany are expected to urge Russia and China in talks on September 2 to consider a fourth round of U.N. sanctions on Iran and the latest IAEA report will help form the basis for the discussions.
In Washington on Friday, a State Department spokesman said Iran's latest moves at the IAEA fell short of what was required. Several diplomats from the six world powers said they were skeptical about Iran's latest move.
To avoid further sanctions, Tehran must stop enrichment, come clean about its past nuclear activities and sit down at the negotiating table, the diplomats said. Iran has repeatedly ruled out halting or freezing its nuclear program.
Western hopes that Iran would negotiate a cap on its nuclear work faded when it quelled unrest over alleged fraud in a June election which returned President Mahmoud Ahmadinejad to power.
But the new head of Iran's Atomic Energy Organization, Ali Akbar Salehi, is seen by analysts as a mild-mannered politician in favor of resolving the nuclear row through talks.
Qashqavi, the Foreign Ministry spokesman, said the Western punitive measures could not stop Iran's nuclear activities.