SEOUL: The recent U.S. extension of sanctions against North Korea was an act of hostility and an outright challenge to an historic summit between the two countries in Singapore last year, Pyongyang's state media said on Wednesday.

The White House extended last week six executive orders containing sanctions imposed over North Korea's nuclear and missile programmes by one year. 

An unidentified North Korean foreign ministry spokesman called the move a "manifestation of the most extreme hostile acts" in a statement carried by the North's official KCNA news agency.

(Reporting by Hyonhee Shin and Jack Kim Editing by Paul Tait) ((hyonhee.shin@thomsonreuters.com; 822 3704 5658; Reuters Messaging: hyonhee.shin.thomsonreuters.com@reuters.net))