AUA, a unit of Deutsche Lufthansa (LHAG.DE), will start service three times a week from August 22 and resume five flights a week in September, a spokesman for the airline said.

It had suspended service on June 15 because it could not be sure of getting its planes refuelled in Iran, which is subject to international sanctions over its disputed nuclear programme.

"There were talks. The supply of fuel is assured again so we can fly again," the spokesman said, declining to identify its local fuel supplier in Tehran.

Other European airlines including Lufthansa had maintained service to Tehran using long-range jets that did not need to refuel for return trips.

In June last year, Iran said it would take action against "inhuman" sanctions that made it harder for its passenger planes to refuel abroad and buy spare parts.

The Islamic state has denied Western allegations that it may be seeking to develop the capability to make nuclear weapons, saying its atomic programme is purely peaceful. (Reporting by Michael Shields; Editing by Elaine Hardcastle)

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