Japan has decided to send a large helicopter carrier to the South China Sea and the Indian Ocean for a second straight year, sources say, in a move that is likely to anger China.

Unnamed sources who had direct knowledge of the plan were cited by Reuters as saying on Wednesday that the Kaga helicopter carrier would start a two-month tour of the South China Sea and the Indian Ocean in September.

“This is part of Japan’s efforts to promote a free and open Indo-Pacific,” one source said.

It would be a second straight year that Japan’s Self-Defense Force would be present in the contested South China Sea.

The Kaga, which is 248 meters long and can operate several helicopters simultaneously, would make stops in Southeast Asian countries such as Indonesia, India, and Sri Lanka, the sources said.

The Kaga will be accompanied by an escort ship and may also conduct ad hoc joint drills with warships from other counties in the region, the sources said.

Japan’s Maritime Self Defense Force, however, refrained to comment.

Japan last year sent Kaga’s sister ship, the Izumo, on a similar tour of the South China Sea and the Indian Ocean.

Tensions

Japan and China are two of the world’s largest economies. The two have a territorial dispute in the East China Sea.

Japan’s planned operations at the South China Sea — where other countries contest territory with China — is likely to provoke Beijing.

The United States, a Japanese ally, regularly holds what it calls freedom of navigation operations in the waters, where trillions of dollars of trade passes through annually.

Beijing guarantees safe passage to ships in the waters and protests to foreign military presence there, saying foreign patrols raise tensions.