Japan says North Korea has rejected scientific findings concerning human remains Pyongyang recently handed over. This response comes as the Japanese foreign minister says that economic sanctions could be imposed against North Korea if the issue of Japanese citizens abducted by North Korea is not resolved.

The Japanese Foreign Ministry says North Korea accuses Tokyo of making up scientific evidence that the remains were not those of two Japanese citizens Pyongyang has admitted kidnapping decades ago.

Japanese officials say North Korea sent a harsh message accusing Tokyo of conspiring against Pyongyang.

Japanese Foreign Minister Nobutaka Machimura on Thursday said economic sanctions against North Korea are an option if the abduction issue is not soon resolved.

But Mr. Machimura says he rejects North Korea's rhetoric that sanctions would be tantamount to declaring war. The foreign minister notes that the United States has sanctions against North Korea but obviously there is no war going on between the two nations.

North Korea has admitted abducting 13 Japanese citizens in the 1970s and '80s to train its spies.

Five were allowed to return to Japan two years ago, but Pyongyang says the rest have died. Japan says that without conclusive evidence of their deaths, it considers them to be alive.

In November, Pyongyang handed over what it said were the remains of two of the abductees. Japanese authorities, however, say genetic tests showed the remains were not those of Megumi Yokota and Kaoru Matsuki.

Mr. Machimura, expressing deepening Japanese frustration, says the government will both apply pressure and pursue talks with North Korea, but it will not continue indefinitely with what he called "meaningless dialogue."

The majority of the Japanese public, according to recent opinion polls, supports sanctions against North Korea. The abduction issue is an emotional one for the country and anger has grown since the test results on the remains were announced.

But some in the Japanese government, including Prime Minister Junichiro Koizumi, appear reluctant to press for sanctions, for fear it would derail efforts to resume multiparty talks about North Korea's nuclear weapons.

There have been three rounds of talks involving the two Koreas, China, the United States, Japan and Russia. They are intended to persuade North Korea to give up efforts to make nuclear weapons.

North Korea refused to attend a scheduled fourth round in September.