North Korea's latest missile provocation will bolster the case for South Korea and the United States to place an advanced missile defense system on the peninsula as it demonstrates the threats from Pyongyang's pursuit of weapons of mass destruction, Seoul's top diplomat said Wednesday.

Earlier in the day, South Korea's Joint Chiefs of Staff said that the North test-fired a mid-range Rodong missile from the western area of the country into waters off its east coast. The U.S. later said that the North fired off two missiles, with one exploding right after launch and the second one landing in the East Sea.

It is seen as a show of force by the North against the plan unveiled by Seoul and Washington in July to deploy a Terminal High Altitude Area Defense here by end-2017 in a bid to counter the North's evolving nuclear and missile threats.

"(The missile launch) is a good example that shows how the North's missile threats can be materializing in reality," Foreign Minister Yun Byung-se told reporters on the sidelines of a forum held in central Seoul. "It is a situation that underlines the need (for us) to deploy THAAD."

He said that the North test-fires missiles always with "multifaceted" reasons behind the launches, saying that the latest one might have been arranged ahead of an upcoming large-scale joint military drill for South Korea and the United States.

The allies plan to conduct the Ulchi Freedom Guardian exercise in mid-August. North Korea has long condemned such drills as a rehearsal for invasion of the country despite repeated assurances from Seoul and Washington that the exercises are purely defensive in nature.

Mentioning the concerns voiced by member countries of the ASEAN Regional Forum held in Laos last week, Yun also said that it clearly demonstrates that the threats from the North are being felt not just by neighboring South Korea but also by many other countries in Asia and in the world. (Yonhap)