Mottaki met in Tokyo with his Japanese counterpart Taro Aso and told him Iran has the right to nuclear technology for "peaceful purposes." The Iranian foreign minister reiterated Tehran's position that it has no intention of seeking nuclear weapons.
Aso had said before the meeting that he would urge Iran to halt its uranium-enrichment program.
Mottaki's visit to Japan came after Iran and Russia agreed in principle on 26 February to form a joint venture to enrich Iranian uranium. It is hoped the deal will allay international fears that Iran may be seeking to develop atomic weapons.