South Korea Ends Commercial Relations with North

South Korea 's president has held a nationwide address to announce stern measures against North Korea. South Korea and the United States say Pyongyang is responsible for sinking a South Korean navy ship.

Photo: South Korea Ends Commercial Relations with North

President Lee Myung-bak on Monday said North Korean must pay for sinking one of South Korea's navy ships, Voice of America reports.

President Lee Myung Bak said in a speech today he will ask the United Nations Security Council to probe the North’s involvement in the attack that killed 46 sailors.

North Korea threatened “strong physical measures” against a South Korean move to resume propaganda broadcasts into the communist country, including shooting at speakers used to carry the messages, Bloomberg says.

According to Reuters, Japanese Prime Minister Yukio Hatoyama said last week that Japan should "be at the forefront" if Seoul sought a U.N. Security Council resolution against North Korea.