Japan expressed "serious concern" to North Korea on Saturday about its reported plan to test-fire a ballistic missile but the Koreans did not respond, the head of Japan's delegation at talks in Beijing was quoted as saying. Earlier, a North Korean official in New York dismissed reports that the secretive country was preparing a missile launch, calling them speculation, Kyodo news agency said. The head of Japan's delegation in the Beijing talks, Akitaka Saiki, had said before they opened that he would raise reports of a planned missile test because it was "quite an important issue for Japan's security", Kyodo reported. Pyongyang was to report to Japan at the talks on progress in its reinvestigation of 10 Japanese who Tokyo says were abducted by the North. Kyodo quoted Song Il Ho, vice director of the North Korean Foreign Ministry's Asian Affairs Department, as telling reporters the two sides held "sincere discussions" and that he talked only about the abduction issue in the session, which lasted 3-1/2 hours. The talks are due to end on Sunday but may carry over to Monday, Kyodo quoted Japanese officials as saying.