Iranian Foreign Minister Mohammad Javad Zarif is visiting Japan from Wednesday.
Japan's Foreign Ministry said Zarif's three-day visit through Friday was quickly arranged at Iran's request. He is to have talks with Japanese Foreign Minister Taro Kono on Thursday, and pay a courtesy call to Prime Minister Shinzo Abe.
They're expected to discuss the situation involving Iran and its nuclear deal, from which the United States withdrew.
The US has dispatched an aircraft carrier to the Middle East apparently to pressure Iran. Tension between Iran and Saudi Arabia is also growing.
Japan's government hopes to avoid deterioration of the regional situation, such as a closure of the Strait of Hormuz, which is vital for Japan's energy supply. It wants to play a role in lessening tension in the region, using its traditional ties with Iran.