Relatives of people kidnapped by North Korea met Tuesday with U.S. Secretary of State Hillary Rodham Clinton, who stressed that international cooperation is key to resolving the long-running problem.

"Clinton said she would think seriously about how to treat the problem, although she avoided discussing details," Shigeo Iizuka, chairman of the Association of the Families of Victims Kidnapped by North Korea, told reporters after the meeting in Tokyo, noting she used both the terms "pressure" and "talks" when mulling future plans.

Clinton told Iizuka and other representatives that she has long been concerned about the issue, which she felt the U.S. should prioritize, Iizuka said.

Iizuka's sister, Yaeko Taguchi, was kidnapped in 1978.

Clinton "said that isolated talks, just between the U.S. and North Korea, or between Japan and North Korea, would not work, because North Korea is a cruel country whose methods she cannot comprehend," Iizuka said, adding she expressed sympathy and inquired about the well-being of the five abductees who were repatriated in 2002.

"I talked to her as mother to mother," said Sakie Yokota, whose daughter, Megumi, was abducted by North Korean agents in 1977 when she was 13.