Japan's Defense Agency chief said Sunday that another North Korean missile launch is expected but doesn't appear imminent.

"According to our analysis, it appears another launch doesn't seem to be coming anytime soon," Defense Chief Fukushiro Nukaga said on the Fuji Television talk show Broadcast 2001. "But there is the possibility they will launch again in the future."

One reason another test doesn't appear imminent is that Wednesday's launch of the long-range Taepondong 2 missile is believed to have ended in failure, and North Korea is likely to take time ironing out glitches before making another attempt, he said.

"They were not satisfied by the results," Nukaga said.

In the meantime, Tokyo wants to speed up efforts to establish a missile defense shield with the United States to guard against the threat posed by North Korea, he added.

When asked whether Japan would request deployment of more U.S. guided missile warships to Japanese waters to bolster the shield, Nukaga said the issue required more study.

"If it makes us more secure and fills out our defense, we should make a decision after consulting with the United States," Nukaga said.

On Saturday, a new U.S. guided missile destroyer, the USS Mustin, docked in Japan, but the U.S. military said the arrival was routine and had been planned months ago and did not come in response to North Korea's test-firing of seven missiles last Wednesday.

At least one of those missiles was believed capable of reaching the U.S. mainland.

In August, Yokosuka also will welcome the USS Shiloh, which last month demonstrated its ability to shoot down missile warheads in a landmark test off Hawaii.

Both the Mustin and the Shiloh are equipped with radar systems that employ Aegis technology, which is geared toward tracking and shooting down enemy missiles. The system was instrumental in identifying and assessing Wednesday's launchings in which all the missiles apparently fell into the Sea of Japan.