The Maritime Self-Defense Force has kicked off its second quadrilateral naval exercise in less than two weeks, with warships — including Japan’s largest flat-topped helicopter carrier Izumo — joining vessels from the Australian, French and U.S. navies in waters west of the Indonesian island of Sumatra.

The joint drills, which began Sunday and are scheduled to run through Wednesday, saw the Izumo and the MSDF destroyer Murasame link up with the French Navy’s Charles de Gaulle aircraft carrier strike group, an Australian Navy frigate and submarine, and a U.S. Navy guided-missile destroyer, the MSDF said in a statement.

It comes on the heels of a multilateral exercise that saw the MSDF sail with ships from the U.S., India and the Philippines navies in the disputed South China Sea.

The multilateral exercises are likely to be interpreted in Beijing as pushback over its moves in the South China Sea, where China has constructed a series of military outposts, some observers say.

The waterway includes vital sea lanes through which about $3 trillion in global trade passes each year. The Philippines, Vietnam, Malaysia, Taiwan and Brunei have overlapping claims in the waters, where the U.S., Chinese, Japanese and some Southeast Asian navies also routinely operate.

Japan has worked to bolster its presence in the South China Sea, deploying the Izumo and Murasame as part of the MSDF’s Indo-Pacific deployment this year, which began April 30 and runs through July 10.

This is the first time the exercises, known as La Perouse, have been held, according to the U.S. Navy, though there are other naval exercises conducted in the region involving the U.S. and multiple militaries.

“La Perouse shows that our maritime forces can work together well anywhere in the Indo-Pacific,” Vice Adm. Phil Sawyer, commander of the U.S. 7th Fleet, said in a statement. “It reflects our shared values, traditions and bonds as like-minded sea services.”

MSDF Rear Adm. Hiroshi Egawa, commander of the Yokosuka, Kanagawa Prefecture-based Escort Flotilla 1, praised the joint drills, saying they would aid Japan’s “Free and Open Indo-Pacific Strategy.”

“The Japan-France-Australia-U.S. multilateral exercise is a great experience. I am looking forward to working with high-end navies together” to improve tactical skills and partnerships, Egawa said in the statement ahead of the exercises. “I believe this exercise will contribute to peace and stability in the Indo-Pacific region.”

Asked if the La Perouse exercises were intended as a message for China, a U.S. Navy spokesman told The Japan Times in an email that was not the case.

“La Perouse is new, but we do multilateral and bilateral exercises like this throughout the year — Malabar, SEACAT, Talisman Saber are a few examples,” said Cmdr. Clay Doss, a spokesman for the U.S. Navy’s Yokosuka-based 7th Fleet. “None of them is a message to a specific country. All of them are about working with our allies and partners. The same is true for exercises in the South China Sea, which the U.S. Navy has operated in, and trained in, for decades.”