The United States and North Korea have blamed each other for rising tensions on the Korean peninsula. The recriminations came at a regional security forum in Vietnam where concerns have been raised about North Korean aggression. At the forum, concerns were also raised about nuclear ambitions in North Korea and Burma.
U.S. Secretary of State Hillary Clinton Friday said North Korea was on a campaign of provocative, dangerous behavior.
Washington and Seoul say North Korea in March torpedoed a South Korean navy ship, killing 46 sailors. Pyongyang denies it was responsible.
Clinton made the comments in Hanoi to an annual meeting of Asia Pacific and Western ministers, including North Korea's.
A spokesman for North Korea's delegation responded by lashing out at weekend plans for a joint U.S.-South Korea military exercise in the Sea of Japan, saying they posed a threat to all of Asia.
Ri Tong Il told journalists the maneuvers planned for Sunday were against North Korean sovereignty and compared them to 19th century gunboat diplomacy.
He referred to North Korea using its official name, the DPRK, or Democratic People's Republic of Korea.
"It is another expression of hostile policy against the DPRK and DPRK position [is] clear. There will be physical response towards this threat," he said.
Representatives from 26 nations and the European Union met in Hanoi for the Association of Southeast Asian Nations' Regional Forum.
Cause for concern
The ministerial-level meetings discuss security and cooperation but were overshadowed by concerns about North Korea and Burma.
At a briefing following the meeting Clinton said it was distressing that North Korea continues to issue threats, causing anxiety among its neighbors and the region. But she said despite Pyongyang's actions Washington was keeping a door open for diplomacy.
"If they are willing to commit themselves, as they did five years ago in 2005, to the irreversible denuclearization that would make the entire Korean peninsula, not just the south but the north as well, free of nuclear weapons, we are willing to meet with them, we're willing to negotiate, to move toward normal relations, economic assistance. We want to help the people of North Korea," she said.
Clinton warned North Korea's proliferation of conventional weapons and nuclear knowledge could lead to a nuclear arms race in the region, which she said was one of the greatest dangers facing the world today.
She said it was critical that Burma's neighbors urge the military government to abide by the nuclear non-proliferation treaty amid reports that the military government may be seeking a nuclear weapon with North Korean help. Burma denies a defector's claim that he worked on a secret nuclear program.
"I also urged Burma to put in place the necessary conditions for credible elections, including releasing all political prisoners, especially Aung San Suu Kyi, respecting basic human rights and ceasing attacks against their ethnic minorities," she said.
Burma is to hold elections this year, the first in two decades, but critics dismiss the polls as a sham designed to keep the military in power.
This week Clinton announced new economic sanctions against Pyongyang. U.S. lawmakers also voted to renew sanctions against Burma for rights violations.
At the ASEAN meeting Clinton also said Washington was willing to help negotiate competing claims over island territories in the South China Sea.
China, Brunei, Malaysia, the Philippines, Taiwan, and Vietnam all claim territory in the sea.
Clinton said the U.S. was willing to help mediate the disputes but that Washington did not support any country's claims.