North Korea remains unresponsive to Seoul’s daily calls after South Korea and the United States wrapped up their combined summertime military exercise on Thursday. 

An official from the Unification Ministry said on Friday that the North did not answer a call made through the liaison office hotline at 9 a.m. There were also no answers on the military lines.

It marks the 18th consecutive day Pyongyang refused communication through the hotlines. It started just after South Korea and the U.S. kicked off preliminary training on August 10 and continued through the main drill that ran from August 16 to 26.

The regime previously severed an inter-Korean military communication channel and passage to the Gaeseong Industrial Complex in the North when the alliance began the regular Key Resolve exercise in March of 2009, but reinstated both a day after the joint drills ended.