Singapore - US Secretary of State Hillary Rodham Clinton said Wednesday said a recent clash between warships from North and South Korea would not affect the decision to send a US special envoy to the Stalinist state.

Ambassador Stephen Bosworth would visit Pyongyang "in the near future" to persuade North Korea to return to international talks on ending its nuclear weapons programme, Clinton said on the sidelines of the summit of the Asia-Pacific Economic Cooperation (APEC).

The naval skirmish "does not in any way affect our decision to send ambassador Bosworth," she said.

"This is an important step that stands on its own," Clinton added. "It is an effort to pave the way for North Korea's return to the six-party process."

"Our expectations on Pyongyang have not changed and will not change," she said.

North Korea abandoned the six-party talks that also include the US, China, Japan, Russia and South Korea earlier this year, but Washington expects Pyongyang to return to negotiations and reaffirm its commitment to a 2005 agreement to dismantle its nuclear weapons programme.

On Tuesday, a North Korean patrol ship was damaged when vessels from the two Koreas exchanged fire. The North's ship crossed the Northern Limit Line, the countries' disputed maritime border in the Yellow Sea, prompting a naval vessel from the South to fire warning shots, South Korea said.

North Korea's military charged the South Korean ships with violating the North's territorial waters by chasing the patrol boat over their border. Pyongyang accused Seoul of a "grave provocation" and demanded an apology.

The sea battle was the first between the two Koreas in seven years.

"We are obviously hoping that the situation does not escalate," said Clinton. (dpa)