ANKARA

The US, South Korean, and Japanese forces on Wednesday held a trilateral missile defense exercise in the international waters of the East Sea, said the South Korean military.

The drill comes after North Korea fired a long-range ballistic missile on Saturday and two short-range ballistic missiles on Monday.

The joint missile defense exercise was held on South Korea's Ulleung Island, Yonhap News Agency reported, quoting the joint chiefs of staff of South Korea.

"Through the maritime missile defense exercise this time, the South, the US and Japan strengthened security cooperation and further solidified their response systems," said the South Korean military.

"This trilateral cooperation is reflective of our shared values and resolve against those who challenge regional stability," it further said.

This was for the second time in the last five months that the three countries held trilateral missile defense drills.

The US and South Korea are also going to stage a combined "table-top" exercise (TTX) at the Pentagon on Wednesday to discuss the scenario of nuclear use by North Korea, according to the agency.

On Sunday, South Korea and the US also held joint air exercises in an apparent response to North Korea’s firing of an intercontinental ballistic missile (ICBM).

On Saturday, North Korea launched the ballistic missile, which remained in the air for 66 minutes, and traveled 900 kilometers (559 miles) with a maximum altitude of 5,700 kilometers (3,541 miles) before landing in the sea off Japan’s west coast.

North Korea on Sunday also warned the US and South Korea that it successfully demonstrated its ability to launch a “fatal nuclear counterattack.”

Meanwhile, South Korean Foreign Ministry summoned a Japanese diplomat in Seoul to lodge a protest over a high-ranking Japanese official’s claim to disputed islets in the east of South Korea.

The ministry told the Japanese diplomat that Dokdo is "historically, geographically and under international law" part of South Korean territory and called for Japan to halt making "unreasonable claims," according to Yonhap News Agency.

Both countries claim sovereignty over the Liancourt Rocks, a group of small islets in the Sea of Japan that are referred to as Dokdo.

*Writing by Islamuddin Sajid