A pro-Pyongyang newspaper pressed Seoul Wednesday to accept an offer from North Korean leader Kim Jong-Il to hold a summit with South Korea's leader.

Ex-US president Jimmy Carter, who visited the communist state late last month, said he received a "personal" written message from Kim.

Carter said the message offered unconditional talks with the United States and South Korea aimed at easing tensions, including a summit with the South's President Lee Myung-Bak.

South Korea has repeatedly said it is willing in principle to hold such a summit. But it was unenthusiastic about Carter's trip and questioned the sincerity of Kim's latest offer.

The Japan-based Choson Sinbo newspaper, which normally reflects the North's official thinking, said Seoul underestimated Carter's mission while the international community took it seriously.

Kim's offer would give Lee "a last chance to correct the direction of his policy", it said, accusing his government of pursuing a policy of confrontation with the North.

The paper also reacted coolly to Lee's latest proposal, made Monday on a visit to Berlin, that Kim attend a nuclear security summit in Seoul next March after first making a firm pledge to give up its nuclear weapons ambitions.

Choson Sinbo said Lee was merely trying to avoid criticism for turning down Pyongyang's bold proposals for dialogue.

Cross-border relations have been icy since the South accused the North of sinking the Cheonan warship in March 2010 with the loss of 46 lives.

The North denies involvement but shelled a South Korean border island last November, killing four people including civilians.

Before any major dialogue takes place, Seoul demands Pyongyang take responsibility for both incidents.

Six-party talks on ending the North's nuclear programmes in return for diplomatic and economic benefits have been stalled since December 2008.

Last November the North disclosed an apparently functional uranium enrichment plant, which could give it a second way to make atomic bombs.

China is pressing to revive the six-party forum and the North has expressed interest. But South Korea and the United States say it should first show it is serious about disarmament and improve cross-border ties.

The talks also involve Japan and Russia.