Australia has joined the United States in stating that China's claims in the South China Sea do not comply with international law in a declaration likely to anger China and put more strain on their deteriorating relations.
The United States this month rejected China's claims to offshore resources in most of the South China Sea, drawing criticism from China which said the US position raised tension in the region.
Australia, in a declaration filed at the United Nations in New York on Friday, said it too rejected China's maritime claims around contested islands in the South China Sea as being inconsistent with the UN Convention on the Law of the Sea.
"Australia rejects China's claim to 'historic rights' or 'maritime rights and interests' as established in the 'long course of historical practice' in the South China Sea," it said.
Australia also said it did not accept China's assertion that its sovereignty over the Paracel Islands and the Spratly Islands was "widely recognised by the international community", citing objections from Vietnam and the Philippines.
China claims 90% of the potentially energy-rich waters but Brunei, Malaysia, the Philippines, Taiwan and Vietnam also lay claim to parts of it.
About $3 trillion worth of trade passes through the waterway each year. China has built bases atop atolls in the region but says its intentions are peaceful.
Australia has long advocated for freedom of navigation in the South China Sea and for all claimants to resolve their differences in compliance with international laws.
Its more outspoken position on China's claims comes after US Secretary of State Mike Pompeo said this month China had offered no coherent legal basis for its ambitions in the South China Sea and for years has been using intimidation against other coastal states.
The world would not allow China to treat the South China Sea as its maritime empire, Pompeo said, adding that the United States would support countries that believed China has violated their maritime claims.
The United States has long opposed China's expansive territorial claims on the South China Sea, sending warships regularly through the strategic waterway to demonstrate freedom of navigation.
Australia's declaration on China's claims comes as its foreign and defence ministers prepare to travel to Washington to attend a bilateral forum on July 28, the government said.
Diplomatic tension between China and Australia has worsened recently over various issues including an Australian call for an international enquiry into the novel coronavirus, which emerged in the Chinese city of Wuhan late last year.