North Korean negotiator Kim Kye Gwan said "a certain agreement" was reached during discussions in Berlin, without giving details, but Hill said he didn't know to what Kim was referring.
Hill earlier called the Berlin talks "very useful."
Hill is now in South Korea to raise support for renewed six-country talks to persuade the North to give up its nuclear program.
The Proliferation Threat
The Arak heavy-water plant in central Iran (Fars)
BENDING THE RULES. Henry Sokolski, executive director of the Nonproliferation Policy Education Center, told an RFE/RL-Radio Free Asia briefing on January 9 that the West is hamstrung in dealing with Iran and North Korea because of the way it has interpreted the international nonproliferation regime to benefit friendly countries like India and Japan.
LISTENListen to the entire briefing (about 90 minutes):
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