China on Tuesday rejected the Philippines' claim to maritime jurisdiction over Chinese territory as illegal, saying its construction and other activities on its own territory are justified and lawful, and vowed to take resolute measures to safeguard its territorial sovereignty and maritime rights and interests.

Foreign Ministry spokesman Guo Jiakun made the remarks at a news conference after the Philippines made "illegal" claims over China's Meiji Reef, Zhubi Reef and Zhongye Island.

Guo said the Nansha Islands, including the three features, are China's inherent territory, and that China's construction and other activities on its own territory are matters within its sovereignty and are entirely justified.

The Philippines' territorial scope is defined by a series of international treaties, and the Nansha Islands have never been part of Philippine territory, Guo stressed.

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Under the international law principle that land sovereignty determines maritime rights, the Philippines' claim of so-called maritime jurisdiction over Chinese territory is illegal, he added.