Taiwan on Tuesday strongly criticized Japan for formally signing a contract to "purchase" parts of the Diaoyu Islands, saying the move will hurt the feelings of the Taiwanese people and escalate tensions in East Asia.

The Japanese government has exchanged an official contract on the purchase of the Diaoyu Islands with the Kurihara family, whom Japan called "the private owner," Japanese media reported on Tuesday morning.

Japan's Cabinet decided earlier in the day to tap reserve funds to purchase three of the five uninhabited islands.

According to the plan, the Japanese central government will pay 2.05 billion yen (26.15 million U.S. dollars) to the Kurihara family in exchange for the islands.

Timothy Yang, a senior Taiwan official, summoned Sumio Tarui, the Japanese envoy in Taipei, to strongly protest Japan's move.

Meanwhile, Taiwan authorities ordered its envoy in Tokyo, Shen Ssu-tsun, to lodge a strong protest with the Japanese government over the issue and to fly back to Taipei as soon as possible to brief on the situation.

Yang told a press conference after his meeting with Tarui that Taiwan harshly condemns Japan's stubborn move.

The Japanese government showed no respect for historical evidence and international conventions by nationalizing the Diaoyu Islands, he said.

He added that Taiwan will not accept any unilateral and illegal move by Japan to "purchase" the islands and will condemn such a move in the harshest term.

He also urged Japan to revoke the purchase contract immediately and warned that Japan will be held accountable for all things resulting from the situation.

Meanwhile, Sean Chen, head of Taiwan's executive body, said Taiwan will not recognize the legitimacy of Japan's move.

Lee Tung-hao, a high-ranking member of the People First Party, added he would propose a draft at the local legislative body to require all related bodies of the Taiwanese authorities to work together to defend the sovereignty of the Diaoyu Islands.

Wu Yu-sheng, a senior member of the ruling Kuomintang Party, proposed a serious protest be lodged with the Japanese government.

He said that Taiwan authorities should strongly protest Japan's move and called on local legislators from both the ruling and opposition parties to jointly inspect the islands to assert sovereignty.

Taiwan leader Ma Ying-jeou said Monday that he was closely monitoring the situation and Taiwan authorities would take appropriate action to deal with it.

He added that Taiwan would not back down if the Japanese government moved ahead to sign the agreement.

Steve Hsia, a senior official of Taiwan authorities, on Monday warned Japan against taking the unilateral move.

He said that Taiwan would not accept Japan's claim of sovereignty over the Diaoyu Islands and Japan's move to "purchase" them was "invalid."

Taiwanese media outlets have reported extensively on the latest developments in the past couple of days.

The United Daily News said on Monday that the latest move by the Chinese mainland to announce the base points and baselines of the territorial waters of Diaoyu Islands is a "strong counter-strike" against Japan.

The United Evening News said in a commentary on Tuesday that Taiwan's public should stand behind the authorities over the issue and "not even an inch should be given up" when defending sovereignty.