The report, citing an unidentified South Korean government source, said the exercise was possibly supervised by North Korean leader Kim Jong-un.
South Korea's military said yesterday that North Korea held major live-fire drills in an area around its eastern coastal town of Wonsan as it marked the anniversary of the founding of its military.
China's special representative for Korean Peninsula affairs, Wu Dawei, held talks Wednesday with his Japanese counterpart, Kenji Kanasugi, amid rising tensions and speculation that North Korea may soon carry out another nuclear or missile test.
The meeting - announced last week and requested by Senate leadership - comes amid the U.S. Navy's bilateral military exercises with South Korea and Japan, and North Korea's live-fire drills to celebrate the anniversary of its military's founding.
A rapid tempo of North Korean weapons testing in the past year has pushed Kim Jong-un's authoritarian nation closer to developing a nuclear-tipped missile that could reach the U.S. mainland.
The announcement to deploy THAAD has also faced opposition from many residents of Seongju county, near the deployment site, and criticism of the decision to deploy it - against the backdrop of the increased militarization of the Korean Peninsula - was a key part of protests that helped bring down former President Park Geun-hye.
Klug reported from Seoul, South Korea.
The Seoul defense ministry said South Korea and the United States made efforts to rapidly secure an operational capability of the THAAD system to respond to what it called the nuclear and missile threats from the Democratic People's Republic of Korea (DPRK).
"We agree among the three of us that we will coordinate all actions - diplomatic, military, economic - regarding North Korea", Yun told reporters.
"China strongly urges the US and South Korea to stop actions that would raise regional tensions as well as harm China's strategic and security interests by canceling the THAAD deployment and withdrawing relevant equipment".
Victoria Neave, Texas Rep, goes on hunger strike over bill
Neave's decision to fast until at least Wednesday, when the House could vote on the bill, is inspired by Cesar Chavez . The bill would also allow the State of Texas to cut funding to institutions that don't comply with the law.
U.S. special representative Joseph Yun said he discussed American policy to "enhance pressure" on Pyongyang "because we really do not believe that North Korea is ready to engage us towards denuclearisation".
The editorial also contains some exasperated hand-wringing about how Beijing can not satisfy the demands of both the United States and North Korea at the same time, which conveys a message that China has gone about as far as it is willing to go with economic pressure against North Korea.
"Our military is closely monitoring the North Korean military's movements", said the statement.
"I think it's safe to say that they will conduct a sixth nuclear test at some point", Jean Lee, a global fellow at Wilson Center and a lecturer on North Korean studies, told CNN. The U.S. Navy also conducted maritime exercises with Japan and South Korea.
North Korea conducted a big live-fire exercise on Tuesday to mark the foundation of its military and a USA submarine docked in South Korea in a show of force amid growing concern over the North's nuclear and missile programs. All 100 senators have been invited to an unprecedented briefing in a building next to the White House that will include President Donald Trump's secretary of state, defense secretary, top general and national intelligence director.
But the system's installation is also upsetting China, the country Trump hopes to work with to rid the North of nuclear weapons.
The Chinese envoy for North Korea says China and Japan have agreed to coordinate in seeking to denuclearize the Korean Peninsula and in urging North Korea to refrain from making further provocations. China, which has grown increasingly frustrated with its ally Pyongyang, and Russian Federation see the system's powerful radars as a security threat.
Residents in the Seongju area, where the battery will be deployed, have also been protesting, anxious that the system's presence will make them a target for North Korea's missiles.
The fear of a USA attack is palpable, and with the Pentagon rushing their THAAD anti-missile system to South Korea, there is a sense that they are planning to do something in short order that would need them to be able to shoot down retaliatory missiles.
U.S. defence leaders and other top officials are to give a classified briefing on North Korea to all senators in an unusual meeting at the White House later Wednesday.