Updated

China's foreign minister on Sunday warned Japan and the United States not to include Taiwan within the scope of their security alliance, saying Beijing would not allow any outside interference in what it considers a purely internal matter.

China (search) insists self-ruling Taiwan is part of its territory and has threatened to attack the island if it declares formal independence.

"Any practice of putting Taiwan directly or indirectly into the scope of Japan-U.S. security cooperation constitutes an encroachment on China's sovereignty and interference into China's internal affairs," Foreign Minister Li Zhaoxing (search) said at a news conference coinciding with the annual meeting of China's legislature.

"The Chinese government and the people are firmly against such activities," he said.

Li repeated Chinese criticisms of the U.S.-Japan alliance as a relic of the Cold War and said such cooperation "ought to be strictly restricted to a bilateral nature."

"If it goes beyond a bilateral scope definitely it will allow uneasiness on the part of Asian countries and also bring about complicating factors to the regional security situation," Li said.

Last month, U.S. and Japanese officials at a meeting in Washington listed "the peaceful resolution" of the Taiwan issue as a strategic objective — a rare mention by Japan of the Taiwan issue. The move drew immediate condemnation from Beijing.

Beijing eyes Japan with deep and bitter suspicion in light of Tokyo's World War II (search) aggression against China as well as a centuries-old rivalry for dominance in East Asia. Taiwan was a colony of Japan in 1895-1945 and maintains friendly ties with Tokyo.

Li also reiterated China's position that it has an "indisputable" historic claim to the uninhabited Diaoyu Islands in the East China Sea (search), which Japan calls Senkaku and administers as part of its territory. China's claim has become a rallying cry for Chinese nationalists, putting Beijing under pressure to take a hard line on the issue.

However, Li added that China believes a solution to the dispute should be sought through negotiations.