By Sky News US Team
US President Barack Obama has authorised fresh sanctions against North Korea as the "first aspect of our response" to the Sony hack.
The measures target three North Korean entities, including a government intelligence agency and a North Korean arms dealer, the Obama administration said.
The US is also imposing sanctions on 10 individuals who work for those entities or the North Korean government.
President Obama said he had ordered the sanctions because of "the provocative, destabilising and repressive actions and policies of the Government of North Korea, including its destructive, coercive cyber-related actions during November and December 2014".
In a letter informing congressional leaders of his executive order, he added the activities "constitute a continuing threat to the national security, foreign policy, and economy of the United States".
"The order is not targeted at the people of North Korea, but rather is aimed at the Government of North Korea and its activities that threaten the United States and others," Mr Obama added.
The US has blamed North Korea for a devastating cyber attack on Sony Pictures that leaked a trove of embarrassing emails and other internal communications, as well as unreleased films.
Pyongyang denied involvement, but has excoriated a comedy by Sony about a CIA plot to kill North Korea's leader.
Sony Pictures initially called off release of the film, The Interview, citing threats of terror attacks against US cinemas.
Mr Obama criticised Sony's decision at the time, and the picture was released last month in movie theatres and online.
The White House declined to comment last week on whether the US was behind a nearly 10-hour shutdown of North Korean websites last week.
Washington already has tough sanctions in place against North Korea over its nuclear programme.
