Washington (CNN) — The president of South Korea has vowed “resolute” measures against North Korea for its alleged attack on a South Korean warship, South Korea's Yonhap News Agency reported Thursday. A five-country committee announced Thursday morning in Seoul that they had concluded a North Korean submarine fired a torpedo that sunk the South Korea warship in March. “(We) will take resolute countermeasures against North Korea and make it admit its wrongdoings through strong international cooperation and return to the international community as a responsible member,” President Lee Myung-bak told Australian Prime Minister Kevin Rudd in phone talks, according to Lee's office, Yonhap reported. The warship, the Cheonan, sank after an explosion ripped it in half on March 26 in disputed waters off North Korea. Forty-six sailors were killed or lost in the incident. North Korea immediately denied the allegation. The North Korean National Defense Commission said in a statement to official television that its navy did not torpedo the South Korean ship, calling South Korean Lee Myung-bak “a traitor,” Yonhap reported. The conclusion came from a joint investigation committee composed of American, Australian, British and Swedish and South Korean experts. The United States has been “deeply and actively involved” in the investigation and “strongly supports its conclusions,” Assistant Secretary of State Kurt Campbell said. Since last month, the U.S. military has believed a North Korean torpedo attack was the most likely cause of the explosion, according to a U.S. military official. The military official said at the time that the blast of an underwater explosion sank the ship, but that the explosive device itself did not come in contact with the hull of the South Korean ship. The United States has a mutual defense treaty with South Korea and Japan to defend “against any aggression,” so if a military confrontation develops, the United States would be responsible for defending South Korea, the official said. “I don't think it will come to that,” the official said. “They know they need to have a response, but there is too much at stake for South Korea to have a confrontation on the Korean peninsula. North Korea has nothing to lose, but South Korea is a serious country with a huge economy.” There are military options for South Korea beyond firing missiles, said John Delury, who studies North and South Korea at the Asia Society. Anything combative would hurt South Korea economically, Delury said, but the country could increase its naval presence along the line that divides South and North Korea in the waters surrounding the countries. He notes that comes with a risk. “Those actions could trigger a conflict,” he noted. “It will be interesting to see how South Korean President Lee [Myung-bak] characterizes this incident,” said Nicholas Szechenyi, deputy director at the Center for Strategic and International Studies, a Washington-based think tank. “A military strike of some sort would be risky because the North Korean regime is so unpredictable,” he said. “You have to be careful about military retaliation because North Korea has thousands of artillery pieces pointed towards the south and could bombard Seoul very quickly.'” The senior U.S. official said that South Korea is expected to “come up with a set of responsible measures” in response, such as action at the U.N. Security Council. Included in those actions could be a resolution condemning the attack, arguing it violates the U.N. charter, Szechenyi said. “The problem is that China is a permanent member of the council and tends to take a very soft position on North Korea, so it is an open question whether the resolution will pass or not,” he said. The Chinese will face a lot of pressure from the United States, but it already sent a clear message of solidarity with North Korea when it recently rolled out the red carpet to receive North Korean leader Kim Jong Il, Delury said. The United States and South Korea could also delay the upcoming transfer of operational control of U.S. and Korean military forces from the United States to South Korea. The transfer is due in April 2012. “It would be more of a political statement to remind North Korea the U.S. is a steadfast ally of South Korea and will come to its defense,” Szechenyi said. Seoul also has limited economic activity with Pyongyang that could be suspended, including a joint industrial complex and some trade. North Korean involvement in the attack also would throw doubt on the future of six-party nuclear diplomacy talks involving the United States, South Korea, China, Japan and Russia. China has been pushing for another round of talks, but the senior U.S. official said there will be less interest now in a quick return to the negotiations. “If the North Koreans are going to continue to misbehave, we have to think whether it makes sense to return to the six-party talks,” the official said. On the other hand, the official suggested the incident might give the United States leverage. China, which hosts the talks and has the closest relationship with North Korea, could be encouraged to get a “better resumption point” in the talks, rather than just pick up where they left off, the official said. Szechenyi suggested South Korea might also ask the United States to put North Korea back on the list of state sponsors of terror, from which it was removed in 2008 as part of the effort to get the country to stop its nuclear program. Putting the country back on the terror list would trigger a number of tough economic sanctions against North Korea, he said. U.S. Secretary of State Hillary Clinton, who will visit Seoul next week, will talk with the South Korean government about the investigation, Assistant Secretary Campbell said. Clinton will also visit Japan and China during her trip, and the North Korean issue is likely to be high on the agenda. Clinton will have “the closest possible consultations with Japan, China and South Korea about the next phase,” added by: onemalefla
