Japan is increasing sea and satellite surveillance of North Korea due to concern that the communist state is preparing to test-fire a ballistic missile for the first time since 1998.

The Japanese government is moving on several fronts to improve its missile-defense system amid a possible threat from North Korea.

Japan's most widely-read paper, the Yomiuri, reports the government had begun preparations for a possible North Korean test-launch of a mid-range Rodong missile in the next few weeks. The missile has a range of up to 1,300 kilometers and could hit most of Japan.

Yomiuri reports that within several months, Tokyo will start deploying an upgrade to its Patriot air defense system to intercept any North Korean missiles in the skies above Japan.

It also says the government will revise pacifist laws to allow the military to engage enemies even before the prime minister orders troops into battle.

Yasuo Fukuda, Japan's government spokesman, did not confirm the report when he met with journalists on Friday. But he noted that Japan needs to be concerned about North Korea's weapons programs and examine whether the North's recent actions will lead to increased threats.

Concerns mounted in October, when U.S. officials said the North had admitted to having a program to enrich uranium, which can be used for nuclear weapons. Since then, Pyongyang has behaved in an increasingly provocative manner, pulling out of the nuclear Non-Proliferation Treaty and restarting banned nuclear facilities. On March second, it intercepted a U.S. spy plane in international waters over the Sea of Japan. The North also test-fired two surface-to-ship missiles into the Sea of Japan in the past three weeks.

Tokyo has deployed a warship off the Korean Peninsula that is equipped with the Aegis radar system, which can track missiles. Japan's Defense Agency says the vessel is carrying out routine duties, but Japanese media reports link the deployment to concerns over North Korea.

Japan also plans to step up surveillance by putting two spy satellites, the country's first, into orbit on March 28. Space agency officials have said that the decision was made, in part, in response to Pyongyang's 1998 missile launch that tested a medium-range missile over Japanese territory and alarmed countries throughout the region.

The latest moves follow testimony to the U.S. Congress that the secretive Stalinist state could be months away from being able to enrich uranium for nuclear weapons, not years as experts had previously estimated. North Korea demands direct talks on the nuclear issue with the United States, but the Bush Administration believes talks should take place in a multi-lateral forum.