Former Prime Minister Tomiichi Murayama on Wednesday announced a suprapartisan Diet group he heads will shelve its planned trip to North Korea, saying now is not the best time to visit the Stalinist state.

Original plans called for a visit to begin this past Sunday, but that was postponed due to political developments surrounding North Korea.

The developments cited by Murayama include U.S. presidential envoy William Perry's visit there in late May, North Korea's recent mission to China, naval disputes between the two Koreas in the Yellow Sea earlier this month and Tuesday's resumption of high-level government talks between the North and the South.

There are also reports that North Korea is preparing to launch another Taepodong missile in the near future.

"Due to these rapidly changing political movements, we cannot set a date for our visit," Murayama said. "We also cannot iron out the differences of opinions (with Pyongyang) over some issues."

The group was hoping to reach a breakthrough in stalled bilateral normalization talks during its visit, but now Murayama does not foresee anything happening in the near future.

"We want to wait and see what happens," he said.

He hinted, however, that his group has received some requests from the North Korean side, such as for resumption of food aid. But Murayama's group has been arguing that its role is to pave the way for normalization talks, adding that it cannot promise food aid.

The group had been holding study meetings since March in hopes of visiting the ailing country.

Its plans have been hampered from the start, first by the intrusion of two North Korean spy ships later that month and then by heated discussions about Pyongyang during Diet debate over bills covering the Japan-U.S. defense cooperation guidelines.