U.S. General B.B. Bell, commander of U.S. Forces in Korea, speaks during a forum with journalists at the National Press Club in Seoul July 2, 2007. North Korea's recent tests of short-range missiles were successful launches of an advanced weapon that can be fired at little notice to strike targets in South Korea, Bell said. [Reuters]

North Korea tested at least three short-range missiles over the past month, with the latest test last week coming as U.N. nuclear inspectors were in the country as a part of a disarmament deal.

"These (missiles) are modern, solid-fuel, which means that they are easy to handle and rapidly capable of being fired," U.S. General B.B. Bell said at a seminar in Seoul.

"These were not failure missile tests. These were successful tests."

The White House said last week it was "deeply troubled" by North Korea's recent test-firing of short-range missiles, but officials in Seoul and at the Pentagon in Washington downplayed them as routine and not provocative.

"What I find very disturbing is that the North continues to test these advanced short-range missiles," Bell said.

North Korea, which tested its first nuclear weapon last year, has more than 1,000 missiles of various ranges, including 800 ballistic missiles, capable of hitting all of South Korea and almost all of Japan, proliferation experts have said.

"One of the biggest threats to peace and stability is the potential capability of North Korea to couple its missile technology with its demonstrated nuclear ability," Bell said.

Proliferation experts say it is unlikely that North Korea has developed the technology to miniaturize nuclear weapons that would allow them to be mounted on a missile.

North Korea defied international warnings and test-fired a barrage of seven ballistic missiles about a year ago, including its long-range Taepodong-2 missile.

Bell said one of the greatest threats South Korea faces is from the massive amount of artillery the North has placed near the border with the South, which includes 250 long-range systems capable of hitting Seoul, only 50 km (30 miles) from the border.

"This is a very real threat which cannot be ignored," Bell said.

He hoped North Korea would live up to pledges it made in a February 13 nuclear deal among the two Koreas, China, Japan, Russia and the United States that called for Pyongyang to start shutting its reactor at Yongbyon, a source of weapons-grade plutonium.