The United States says that various punitive measures on North Korea in relation to the Cheonan case are being considered, including sending the case to the United Nations Security Council.

White House press secretary Robert Gibbs on Thursday told a regular news briefing that due to the North's torpedo attack on the Cheonan, Pyongyang will be further isolated from the international community.

U.S. State Department spokesman Philip Crowley also told a regular news briefing that the North's torpedo attack is a serious provocation and that there will be consequences.

Crowley added that Washington has the ability and authority to take punitive measures on its own against the North in sectors such as finance.

On redesignating the North as a state sponsor of terrorism, the U.S. said that it is possible, but that there is a need to determine whether the North's attack legally constitutes an act of terrorism.

Meanwhile, U.S. Secretary of State Hillary Clinton has launched a tour of Asia that will bring her to Japan, China and South Korea.