U.S. President Barack Obama said his administration and the U.S. military are "fully prepared for any contingencies" involving North Korea -- including the possible launch of a long-range missile toward Hawaii.
In a television interview with CBS News that aired Monday, Mr. Obama said he hopes that Pyongyang will take a path toward rejoining the international community. But he said his administration will not reward "belligerence and provocation."
His comments followed reports that North Korea plans to fire a ballistic missile toward Hawaii in early July, and as U.S. Navy destroyer, the USS John S. McCain, tracked a North Korean ship suspected of smuggling missiles or related parts in violation of United Nations sanctions.
Reports citing unidentified intelligence sources in South Korea said the vessel, the Kang Nam, appears to be heading to Burma by way of Singapore.
Also Monday, the newspaper of North Korea's ruling party, Rodong Sinmun, described the country as a "proud nuclear power" and threatened to hit back at the United States if attacked.
South Korean Unification Minster Hyun In-taek told the Reuters news agency that the North's recent provocative actions are related to rising domestic social unrest and a possible succession by leader Kim Jong Il.
The Kang Nam is the first North Korean ship to be monitored under the terms of a U.N. Security Council resolution adopted earlier this month.
The resolution authorizes U.N. members to inspect North Korean cargo ships for illicit missile-related technology. North Korea has said it would consider any such move an act of war.
The U.S. military has not indicated any plans to search the vessel, which belongs to a fleet of ships that U.S. officials say have been used in the past to transport weapons.
Some information for this report was provided by AP.