Prime Minister Junichiro Koizumi said Friday that Japan and China need to strengthen their "mutually complementary" economic ties, denying that China is an economic threat to Japan.

"To advance reform and mutual interdependence between Japan and China, in a manner that is harmonious with reforms of other Asian nations -- that is the way to develop a wider cooperation in Asia as a whole," Koizumi said in a keynote speech at the first annual conference of the Boao Forum for Asia.

Speaking after Chinese Premier Zhu Rongji delivered the day's first keynote speech, Koizumi brushed off concern over Beijing becoming a "threat" with its rapid economic growth.

"Some see the economic development of China as a threat. I do not," Koizumi said. "I believe a rising economic tide and expansion of the market in China will stimulate competition and will prove to be a tremendous opportunity for the world economy as a whole."