An IAEA delegation visiting Iran can choose to extend its stay beyond the three days originally planned if it wishes, Iranian Foreign Minister Ali Akbar Salehi said on Monday, according to the official IRNA news agency.

"We are very optimistic on the results of the IAEA trip. They are here for a three-day trip, and if they want, it (the mission) could be extended," Salehi was quoted by IRNA as telling Turkish broadcaster TRT in an interview in Addis Ababa, where he was attending an African Union summit.

Salehi also urged the European Union and the United States to "replace their policy of sanctions with interaction" with the Islamic republic.

A six-person team of senior inspectors and officials from the International Atomic Energy Agency, the UN nuclear watchdog, began their visit to Iran on Sunday amid high international tensions over Tehran's nuclear activities.

The visit, led by IAEA chief inspector Herman Nackaerts and including the agency's deputy director general, was due to wrap up on Tuesday.

It was not known which Iranian officials the IAEA team was speaking with, nor was it confirmed whether it was carrying out inspections of suspect sites.

The visit is seen as an opportunity to defuse tensions between Iran and the West that have soared since a November IAEA report that strongly suggested Tehran was researching nuclear weapons. Iran has dismissed the report as biased.

Iran's government has repeatedly denied that its nuclear activities are other than peaceful, and it has asserted its rights to uranium enrichment and atomic energy as a signatory of the Nuclear non-Proliferation Treaty (NPT) that the IAEA oversees.

Salehi underlined that stance to reporters in Addis Ababa.

"No one has the right to tell us to halt enrichment. Enrichment is our right based on the NPT and our being an official member of IAEA, and no one has the right to ask us to stop this legal activity," he said, according to IRNA.

The minister said Iran "fully adheres" to IAEA regulations and would maintain "transparency" in its activities.

"The inspection delegation can visit any of our nuclear sites it requests to visit," he said.