North Korea's chief nuclear negotiator Kim Kye-kwan says his country will stop nuclear activities in Yongbyon when all sanctions are lifted on its frozen assets at Macao's Banco Delta Asia.

In his keynote speech at the six-way nuclear talks that resumed Monday in Beijing, Kim reportedly stressed the "words for words, action for action" principle agreed in earlier rounds.

A source close to the talks also quoted him as saying that spring has arrived in Beijing, which is seen as conveying Pyongyang's intent to implement the initial dismantlement steps and its satisfaction at the U.S. announcement. Earlier that day, Washington said it would allow the release of all 25 million dollars held in North Korean accounts frozen at BDA since September 2005.

Kim's attendance at the sixth round of talks on Monday was his first public appearance since arriving in Beijing Saturday.