North Korean state media on Friday fired back at the new U.S. ban on visiting Pyongyang, calling it a “sordid” effort to inhibit human exchanges. “Our doors are always open for all Americans who visit our country out of good will and wish to see our reality,” a foreign ministry spokesman said. The U.S. State Department announced this week that the ban will take effect Sept. 1. Humanitarian workers and journalists can apply for exceptions. The travel restriction follows the June death of Otto Warmbier, an Ohio college student was sentenced to 15 years of hard labor in North Korea for allegedly stealing a poster.