A Chinese mainland spokesman urged people across the Taiwan Straits on Wednesday to safeguard the Diaoyu Islands and the South China Sea islands as China's ancestral possessions.

The mainland also hopes to maintain the peaceful development of relations across the Straits, Ma Xiaoguang, spokesman for the State Council's Taiwan Affairs Office, said during a news conference when asked about remarks by former Taiwan leader Ma Ying-jeou.

Ma Ying-jeou had said that the Diaoyu Islands in the East China Sea and islands in the South China Sea are China's inherent territory and that Japan's territorial claim to the Diaoyu Islands amounts to an act of theft. He also said peace is highly important to cross-Straits relations and will bring prosperity.