SEOUL: North Korea has sacked two top officials, including a once key aide to leader Kim Jong-Il, blaming them for worsening cross-border ties with South Korea, a South Korean newspaper said Monday.

Yu Yong-Sun, a 68-year-old Buddhist leader, has replaced Choe Sung-Chol, deputy director of the United Front Department of the North Korean Workers' Party, an influential state organisation, the JoongAng Daily said.

Choe has stepped down because of his failure to accurately assess South Korea's presidential election in December, 2007, and the direction of inter-Korean relations, it said.

Choe, once deeply trusted by North leader Kim Jong-Il, played a crucial role in arranging the second inter-Korean summit in 2007, the daily said.

It quoted an unidentified government official as saying Kwon Ho-Ung, the North's chief negotiator for high-level talks with South Korea, also stepped down and has been put under house arrest.

The South's unification ministry, refused to confirm the report saying only that Yu had visited Seoul for inter-Korean talks.

Inter-Korean ties began to worsen after South Korea's conservative President Lee Myung-Bak took office in February last year.

Lee rolled back his liberal predecessors' engagement policy and linked major economic assistance to the North's willingness to make progress in denuclearisation and openness.

The hardline communist country has stopped all government-level talks, blaming what it calls Seoul's confrontational policy.

Last month it expelled hundreds of South Korean workers from a Seoul-funded joint industrial estate and imposed strict border controls.

- AFP/yb