South Korean protestors hold up banners reading 'Kim Jong-Un Out!' during a rally denouncing North Korea's nuclear test, in Seoul on February 22, 2013. - 

North Korea's government has said it reserves the right to carry out a pre-emptive nuclear attack against the United States ahead of a U.N. vote on tighter sanctions against the communist regime.

The Security Council meets later today to approve fresh economic sanctions against Pyongyang after the country carried out an unauthorized nuclear test on February 12.

The BBC's Lucy Williamson in Seoul says the sanctions will target "the funding that the U.S. believes is going into North Korea's military program." The new set of restrictions will focus on the country's international banking operations.

Earlier this week, North Korea also threatened to scrap the 60-year truce which ended the Korean War.