North Korea is cutting off communication with South Korea claiming this as the first step against their proclaimed enemy. This is a result of the South throwing leaflets of propaganda according to North Korean officials. North Koreans are only allowed news fed to them through officials. Stopping communication includes the daily phone calls between the leaders along with any hotline between the two countries. There is still no signed peace treaty after the 1950 to 1953 Korean War.

Source: By Bjørn Christian Tørrissen - Own work by uploader, http://bjornfree.com/kim/, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=32400550