Ministry spokesman Esmaeil Baqaei said the meeting with the International Atomic Energy Agency was "part of our ongoing engagement with the agency".

The meeting in the Austrian capital comes after Gharibabadi took part in talks with his Russian and Chinese counterparts in Beijing on Friday.

"As threats against Iran's peaceful nuclear facilities have increased, it is natural for us to intensify consultations with the IAEA," Baqaei said.

On March 7, US President Donald Trump said he had written to Iran's supreme leader Ayatollah Ali Khamenei urging new talks on the country's nuclear programme but warning of possible military action if it refuses.

For decades, Western countries led by the United States have suspected Tehran of seeking to develop nuclear weapons.

Iran rejects these claims, insisting its nuclear activities are solely for peaceful purposes, including energy production.

In 2015, Iran signed an agreement with the five permanent members of the UN Security Council -- Britain, China, France, Russia and the United States -- plus Germany to limit its nuclear activities.

Trump unilaterally withdrew the United States from the deal in 2018.

In recent months, Iran has held several rounds of talks with Britain, France and Germany in a bid to revive the agreement, which had lifted sanctions on Tehran in exchange for curbs on its nuclear activities.