President Obama Sanctions North Korea After Sony Cyberattack

The White House says North Korean attack was a threat to national security.

Officials say this is the first instance the US government has imposed sanctions in response to a direct cyber-attack on a U.S. company.

Some cyber security experts have questioned whether North Korea was responsible for the Sony hack, but an administration official said the U.S. remains "very confident in the attribution."

Before leaving for his Hawaii vacation, the president had said he would respond to the attack “proportionally” in a time and manner of his choosing. Today's action is “the first aspect of our response,” White House spokesman Josh Earnest said in a statement.

Officials would not say whether that statement should be read as a denial that the U.S. was involved in the outages of North Korea's internet during the past week. “Not going to comment on what may or may not be happening," said one administration official. "You should see this for what it is – the first step in our proportional response."

The order authorizes the Treasury Department to shutdown access to the U.S. financial system, prohibiting transactions and freezing assets, for specific officials and entities of the DPRK and anyone who supports them.

The new U.S. sanctions are not the first imposed against North Korea.

President Obama has previously authorized three rounds of restrictions on the DRPK and its nationals – in 2008, 2010 and 2011 -- mostly related to noncompliance with UN resolutions related to the country’s nuclear activities.