Japan's Self-Defense Forces and the militaries of the United States and South Korea have begun their trilateral exercise in the East China Sea.

Japan's Defense Ministry says the Freedom Edge exercise that began on Wednesday is the second following the first round in June of this year.

Seven warships from the three countries, including the US Navy's nuclear-powered aircraft carrier USS George Washington, will take part in the exercise, as well as stealth fighter jets and patrol aircraft.

The multi-domain exercise will cover areas such as air defense, ballistic missile defense and anti-submarine warfare.

The Defense Ministry said the exercise aims to promote the interoperability of Japanese, US and South Korean forces for peace and stability in the Indo-Pacific, including the Korean Peninsula.

It also stressed that the exercise continues to demonstrate the three countries' defense readiness and firm determination to protect freedom.

The three countries apparently want to showcase their partnership as North Korea repeatedly fires ballistic missiles and China asserts its presence in the region.

At the time of the previous Freedom Edge exercise in June, North Korea warned that such provocative actions could have fatal consequences.