U.S.-North Korean relations have worsened once again, this time over a confrontation between U.S. and North Korean aircraft. As Newsfile?s David Cohler reports, the incident came as the Pentagon moved to strengthen its forces near the Korean peninsula.

The Pentagon says the United States is sending two dozen B-1 and B-52 long-range bombers to the Western Pacific as a further deterrent to North Korea. The deployment comes amid heightened tensions with Pyongyang, fuelled this past weekend by the interception of a U.S. RC-135 spy plane over the Sea of Japan by North Korean fighter jets. Officials say the bomber redeployment was decided before the incident, but even so it brought a sharp rebuke from State Department Spokesman Richard Boucher:

"It's not in North Korea's interest to continue down this track, to continue movement in the wrong direction, to continue finding steps of whatever nature to make the problem more difficult."

In South Korea, where U.S. and Korean forces are conducting joint maneuvers, Seoul's minister of reunification said Wednesday the U.S. has no plans for a preemptive attack on North Korea. Pyongyang, meanwhile, once again called on Washington to sign a peace treaty promising not to launch such an attack.