South Korea's foreign minister said on Saturday the North had failed to provide evidence it is serious about abandoning its nuclear programme, a condition Seoul has imposed for resuming dialogue with Pyongyang.
Foreign Minister Kim Sung-hwan made his remarks after a new call from Pyongyang to respond to its "proposal of good faith" to restart talks it says have no conditions attached.
"Although North Korea has been proposing dialogue for this and that, they need to take responsible steps as regards to the sinking of Cheonan and the shelling of Yeonpyeong Island first of all," Kim told a news conference alongside his Japanese counterpart.
He was referring to two events last year which boosted tension on the peninsula -- the sinking of a southern naval vessel -- blamed on the North which denies all involvement -- and the North's deadly bombardment of a southern island.
"We have said we needed to confirm North Korea's sincerity about denuclearisation, but North Korea has yet to respond to it. (South Korea is) waiting to see how North Korea will respond to that matter."
The reclusive North has appealed almost daily for talks with the South since the New Year, but Seoul has dismissed Pyongyang's peace overtures as "insincere" and "propaganda".
US Defense Secretary Robert Gates this week suggested the six-party talks on Korea -- including the two Koreas, the United States, China, japan and Russia -- could resume if the North ended provocative actions. But he said there was no sign of that for the moment.
Late on Friday, the North's Committee for the Peaceful Reunification told the official KCNA news agency there were no grounds for the South to turn down its proposals for dialogue, given that there were no conditions attached.
"As far as "sincerity" is concerned, there is no such sincere proposal as the one advanced by the North as it clarified that it is ready to meet anyone anytime and anywhere without any precondition to (ease) the grave situation prevailing on the Korean Peninsula and improve the North-South relations," the committee said.
Japanese Foreign Minister Seiji Maehara told reporters he backed the South's stance and called for the North to take actions to show its resolve to denuclearise.
Maehara repeated that Japan, South Korea and the United States would cooperate closely in dealing with the North's nuclear and missile programmes, and said talks between the Koreas should precede any Japanese dialogue with North Korea.