"We are obviously hoping that the situation does not escalate and we are encouraged by the calm reaction that has been present up until now," Clinton said in a news conference in Singapore.

"We are certainly counseling calm and caution when it comes to any kind of dispute, especially one that can cause repercussions and damage that could be quite difficult to contend with," she said.

She added that the United States will go ahead with a planned visit by Stephen Bosworth, special representative for North Korean policy, to Pyongyang in an effort to persuade the North to return to the six- party talks on ending its nuclear programs.

Warships from North and South Korea skirmished in the Yellow Sea off the west coast of the Korean peninsula on Tuesday. The area where the incident occurred is close to where the countries engaged in deadly skirmishes in 1999 and 2002.

Clinton is in Singapore to attend a ministerial meeting to prepare for the Nov. 14-15 annual summit of leaders from the Asia-Pacific Economic Cooperation forum, which U.S. President Barack Obama will be participating in.