HANOI, Vietnam -- North Korea on Friday threatened the United States and South Korea with a "physical response" to planned weekend naval exercises as tensions with the communist nation rose in the aftermath of the sinking of a South Korean warship blamed on the North.
In Vietnam for a Southeast Asian regional security forum, Secretary of State Hillary Clinton and a North Korean official traded barbs over the ship incident, the upcoming military drills and the imposition of new U.S. sanctions against the North.
The spokesman for the North Korean delegation to the talks, Ri Tong Il, repeated Pyongyang's denial of responsibility for the March sinking of the ship that killed 46 South Korean sailors and said the upcoming military drills were a violation of its sovereignty that harkened back to the days of 19th-century "gunboat diplomacy."
The exercises will be "another expression of hostile policy against" North Korea. "There will be physical response against the threat imposed by the United States militarily," Ri told reporters in Hanoi.
Shortly before he spoke, Clinton had lashed out against belligerent acts by the North, warning that it must reverse a "campaign of provocative, dangerous behavior" if it wants improved relations with its neighbors and the United States.
She said stability in the region, particularly on the Korean peninsula, depends in large part on convincing an "isolated and belligerent" North Korea to alter course and return to nuclear disarmament talks.
Peaceful resolution of the issues on the Korean peninsula will be possible only if North Korea fundamentally changes its behavior, Clinton told the gathering of top officials from the 10 members of the Association of Southeast Asian Nations and countries with major interests in the area like the U.S., China, Japan, North and South Korea and Russia.
There was no sign that members of the U.S. and North Korean delegations would meet or even cross paths at the annual security forum, which has in the past been a venue for rare talks between the two sides.
The U.S.-led military command monitoring the cease-fire on the Korean peninsula confronted North Korea on Friday about the deadly sinking of Cheonan warship, calling it a violation of the 1953 armistice.
Colonels from the U.N. Command, who met at the border with counterparts from Pyongyang's Korean People's Army, reminded North Korea of the U.N. Security Council order to honor the truce. Officers also proposed a joint task force to discuss the "armistice violations," the military commission said in a statement.
The 100-minute talks took place at the "truce village" of Panmunjom inside the Demilitarized Zone dividing the two Koreas and marked the second round of talks since the Cheonan went down off the Koreas' west coast on March 26. The two sides tentatively agreed to meet again next Thursday, the U.N. Command said.
On Wednesday, Clinton announced in the South Korean capital that the U.S. would slap new sanctions on the North to stifle its nuclear ambitions and punish it for the sinking of the South Korean ship. The penalties will target the country's elite by taking aim at illicit activities, such as counterfeiting cigarettes and cash and money laundering.
Clinton was in Seoul to show support for South Korea along with U.S. Defense Secretary Robert Gates.
In addition to North Korea's behavior and its nuclear program, Clinton raised concerns about potential atomic collaboration between the North and Myanmar, also known as Burma, which is restricted by U.N. agreements.
Numerous reports in past months have suggested that Myanmar's military rulers are attempting to develop nuclear weapons with North Korean help.
Clinton said "recent events" had called into question Myanmar's pledges to abide by its international commitments, including U.N. sanctions, the requirements of its nuclear watchdog, the International Atomic Energy Agency, and the Nuclear Non-Proliferation Treaty. She did not elaborate but on Thursday mentioned in passing that a North Korean ship carrying military equipment had recently docked in Myanmar.
"It is critical that Burma hear from you, its neighbors, about the need to comply with" those obligation, Clinton told the forum.
She also hit out on Myanmar's human rights record, saying the U.S. is "deeply concerned about the oppression taking place" there against the regime's political opponents and minority groups. Myanmar has said it will hold elections at an as yet unannounced date later this year but U.S. officials say they don't believe the vote will be free or fair.
"We urge Burma to put in place the necessary conditions for credible elections, including releasing all political prisoners, respecting basic human rights and ceasing attacks against ethnic minorities," Clinton said. The U.S. has repeatedly called for Myanmar to release detained Nobel Peace laureate and democracy advocate Aung San Suu Kyi, whose party's landslide victory in 1990 elections was annulled by the military.
Clinton's comments on Myanmar echoed those of previous U.S. administrations but they come as President Barack Obama has made a push for expanded engagement with Southeast Asia. Clinton is to sign the Association of Southeast Asian Nation's Treaty of Amity and Cooperation, something the Bush administration had refused to do.
In an indication of that increased involvement in the region, Clinton said "the United States has a national interest" in resolving conflicting claims over the Spratly and Paracel island chains in the South China Sea, particularly between China and Vietnam.
She said the disputes interfere with maritime commerce, hamper access to international waters in the area and undermine the U.N. law of the sea.
Her comments are likely to anger China, which asserts sovereignty over the whole South China Sea, but Clinton said the U.S. did not support any country's sovereignty over the islands. She said the U.S. is willing to work with the all the parties, including Vietnam, Taiwan, Malaysia, Brunei, and the Philippines, to help negotiate an end to the disputes.