WASHINGTON - The United States is ready to engage in dialogue with Democratic People's Republic of Korea, but only if Pyongyang is prepared for "genuine" negotiations and commits to giving up its nuclear ambitions, US Vice-President Joe Biden said on Thursday.

Biden, who gave a speech on US policy on Asia before a visit next week to India and Singapore, also encouraged China and the 10-member Association of Southeast Asian Nations (ASEAN) to speed up talks to resolve a long dispute over boundaries in the South China Sea.

"Economic growth critically depends on peace and stability," Biden said. "It's critical that all nations have a clear understanding of what constitutes acceptable international behavior."

DPRK offered talks with Washington after tensions spiked earlier this year when Pyongyang threatened the United States and Republic of Korea with a nuclear strike.

Biden, who plays a leading role in US foreign policy, chuckled about the offer.

"As my mother would say, 'I've seen this movie before,'" Biden said. "We are ready, but only - only - if DPRK is prepared to engage in genuine negotiations."

Biden said the United States would reject what he described as DPRK's "pattern of provoking a crisis and then insisting they be rewarded in order to cease and desist," followed by a return to "their nuclear march."

On the long-simmering dispute over the oil-rich South China Sea, China has been talking with its ASEAN counterparts.

"I encourage China and ASEAN to work even more quickly to reach an agreement on a code of conduct for the South China Sea," Biden said.