Japan is considering additional measures against North Korea after the UN Security Council voted unanimously to impose sanctions on Pyongyang, Prime Minister Shinzo Abe said yesterday.
"We were able to send a strong message that the international community will not tolerate North Korea's owning nuclear weapons," Abe told reporters.
Japan's Foreign Ministry said Tokyo will work closely with other countries in implementing the UN resolution.
"North Korea must take very seriously the concerns of the international community ... and take concrete measures to resolve the issue," the ministry said in a statement.
Asked if Japan would consider imposing additional sanctions, Abe said, "We are already considering them, and we want to make a final decision," without elaborating.
On Friday, Japan's Cabinet approved closing ports to North Korean ships and banning trade with the North. The steps took effect at midnight on Friday.
The government on Wednesday barred all North Korean citizens from entry, except those already living in Japan.
All the measures are to last six months, officials said.
Tokyo already had limited sanctions in place against North Korea, imposed after it test-fired seven missiles into waters between Japan and the Korean Peninsula in July.
Those measures included banning the Mangyongbong-92 -- a North Korean ferry that served as a major trade conduit between the countries -- from entering Japanese waters.
Last month, Japan also banned fund transfers and overseas remittances by 15 groups and one individual suspected of having links to North Korean weapons programs.
The Nihon Keizai Shimbun said yesterday that Japan plans to increase the number of groups and individuals subject to such financial sanctions.
It also plans to ban exports of luxury goods to North Korea in line with the UN resolution, the newspaper said, without naming its sources.
Foreign Minister Taro Aso said Japan will look into ways to cooperate in international cargo inspections in response to the resolution, which calls on countries to inspect cargo leaving and arriving in North Korea to prevent any illegal trafficking of unconventional weapons or ballistic missiles.
Meanwhile, Japan's ruling party policy chief said yesterday that Japan needs to discuss whether it should possess nuclear weapons in response to North Korea's claimed nuclear test.
Shoichi Nakagawa, chairman of the Liberal Democratic Party (LDP)'s Policy Research Council, said Japan will adhere to its policy of not arming itself with nuclear weapons, but added that a debate on the issue necessary.
"We need to find a way to prevent Japan from coming under attack," Nakagawa told a television program, referring to what Tokyo should do following the reported North Korean nuclear test.
"There is argument that nuclear weapons are one such option. I want to make clear that I am not the one saying this, and Japan will stick to its non-nuclear principles, but we need to have active discussions," he said.
Nakagawa said the Constitution does not prohibit the possession of nuclear arms, adding that having such weapons could reduce or remove the risk of being attacked.
While some analysts have pointed out the possibility of Japan -- the only nation to suffer an atomic bombing -- seeking nuclear weapons in response to North Korea's announced nuclear test, Japanese Prime Minister Shinzo Abe has flatly rejected the idea.