Tokyo, Japan (CNN) -- The United States needs evidence of a serious commitment from North Korea before resuming six-party talks aimed at resolving the North's nuclear arms standoff, the U.S. special envoy on North Korea policy said Wednesday in Tokyo.
"We are looking for evidence that North Korea now regards the possibility of negotiations seriously. We are not interested in negotiation just for the sake of talking," envoy Stephen Bosworth said. "We want talks to lead to specific and concrete results."
Bosworth made his comments before leaving Tokyo for Beijing, China, for the last leg of his trip in Asia. He visited South Korea and Japan to meet with his counterparts to discuss denuclearization and other policies related to North Korea.
The six-party talks will not resume in the next few weeks, because building a consensus among the nations will take time, he said.
The talks involve the United States, North Korea, China, South Korea, Japan and Russia. Dialogue halted last year after the U.N. Security Council condemned North Korea's launch of a long-range rocket, saying it violated a resolution banning ballistic missile testing. The North expelled U.S. nuclear experts and U.N. nuclear inspectors after the rebuke.
Signs point to improved relations between South and North Korea, Bosworth said.
The bilateral relationship had worsened with the sinking of a South Korean warship in March. Seoul blamed the North for the sinking. A South Korean report, whose findings have been endorsed by the United States, say a North Korean submarine sank the Cheonan warship with a torpedo, killing 46 sailors. North Korea denies sinking the ship.
Pyongyang on Friday proposed to Seoul the resumption of cross-border reunions of families separated by the Korean War, according to the Yonhap news agency.