Sept. 16 (Bloomberg) -- A North Korea engine test for a long-range missile would violate an October 2006 United Nations Security Council resolution passed after the North Asian country set off an underground nuclear explosion, the U.S. said.

State Department spokesman Sean McCormack said he couldn't confirm media reports that North Korea tested the missile engine. The work occurred at a site still under construction, demonstrating part of the base is already operational, South Korea's Chosun Ilbo newspaper reported.

``Any ballistic missile activity of the kind reported would not be permitted'' under Security Council resolution 1718, McCormack told reporters in Washington today. The measure barred the provision of nuclear technology, large-scale weapons and luxury goods to be sold to North Korea and permitted cargo inspections to carry out the prohibition.

The possible engine test might be a sign that North Korea is backtracking on a pledge to cooperate with five other nations seeking an end to the country's nuclear-weapons effort. The North Korean regime has failed to deliver a plan to verify steps to shut down the program.

The engine test at the Dongchang-li base in North Pyongan Province, which is expected to be completed by 2009, also shows that North Korea is continuing to develop long-range missiles, the newspaper reported today, without saying where it obtained the information.

The ignition test earlier this year may have been carried out on a Taepodong-2 missile, which has a range of 6,700 kilometers (almost 4,200 miles).

South Korean Defense Minister Lee Sang Hee told lawmakers on Sept. 11 the government has been aware of the site ``for some time'' and that North Korea has completed about 80 percent of the work there, according to a legislator who attended the briefing and declined to be identified.

To contact the reporter on this story: Viola Gienger in Washington at vgienger@bloomberg.net; Heejin Koo in Seoul at hjkoo@bloomberg.net.

Last Updated: September 16, 2008 13:54 EDT