Current interpretations allow Japanese troops to defend themselves or allies only if directly fired upon; operate only in non-combat zones; and take part in such activities as reconstruction and logistical support. 

Japanese analysts said policy changes may be made through government clarifications rather than revising the constitution.

North Korea's nuclear test has raised speculation that Japan will seek to adopt its own nuclear programme.

A leading member of Abe's ruling Liberal Democratic party last month called for greater public debate on whether Japan should acquire nuclear weapons.

Non-nuclear

Since World War Two Japan's military have
been restricted to self-defence role
Abe, who took office in September 26, said that Japan would stick to its non-nuclear policy, but he added that he could not stop citizens from expressing their views.
 
"For the general public to discuss this matter ... is the freedom of the Japanese people. I am not in a position of restricting that."

Also on Tuesday, Abe pledged to strengthen Japan's security alliance with the US during his first official meeting with George Bush, the US president, at the Asia Pacific Economic Co-operation (Apec) summit in Vietnam this weekend.

Abe said he would stress the need to maintain a strong line on North Korea.

Abe has called for international sanctions against North Korea for conducting its nuclear test. He has also advocated multilateral talks to dissuade Pyongyang from trying to pursue its nuclear weapons programme.