BEIJING China said on Tuesday it was waiting for an official word on why Japan plans to send its largest warship on a three-month tour through the South China Sea, but that it hopes Japan can be responsible.
China claims almost all the disputed waters and its growing military presence has fuelled concern in Japan and the West, with the United States holding regular air and naval patrols to ensure freedom of navigation.
The Izumo helicopter carrier, commissioned only two years ago, will make stops in Singapore, Indonesia, the Philippines and Sri Lanka before joining the Malabar joint naval exercise with Indian and U.S. naval vessels in the Indian Ocean in July, sources told Reuters.
Chinese Foreign Ministry spokeswoman Hua Chunying said she did not know if the ship was going to visit countries in Southeast Asia or if there was another aim.
"We have not yet heard what Japan says officially," she told a daily news briefing.
"If it's only a normal visit, going to several countries, and passing normally through the South China Sea, then we've got no objections, and we hope this kind of normal exchange between relevant countries can play a role promoting regional peace and stability," Hua said.
"But if going to the South China Sea has different intentions, then that's a different matter," she added.
Japan had been stirring up trouble on the South China Sea issue of late, and China hoped it can play a constructive role in peace and stability, Hua said.
Taiwan, Malaysia, Vietnam, the Philippines and Brunei also claim parts of the sea which has rich fishing grounds, oil and gas deposits and through which around $5 trillion of global sea-borne trade passes each year.
Japan does not have any claim to the waters, but has a separate maritime dispute with China in the East China Sea.
(Reporting by Ben Blanchard; Editing by Nick Macfie)