The newly restored cross-border hotline with North Korea is operating smoothly, South Korean officials said Saturday, months after it was disconnected amid heightened geopolitical tensions on the peninsula earlier in the year. 
   
The previous day's restoration of the military hotline on their west coast came as the two Koreas are working toward reopening a shuttered joint industrial park in the North Korean border city of Kaesong. The North severed the line in late March amid heightened tensions on the Korean Peninsula following its third nuclear test the previous month.
   
"The military hotline is confirmed fully restored as a test call via fiber-optic cables was successfully made," said an official at Seoul's defense ministry.
   
The first test call was made on Friday as the two sides agreed a day earlier to restore the military communication line as a preparatory step to restarting the Kaesong Industrial Complex, which has remained suspended since April after the North's unilateral withdrawal of all its workers from the complex.
   
The restoration of the hotline will accelerate the process to normalize operations at the joint park as South Koreans are now allowed to stay there overnight to check on and repair facilities that had been left idle for months.
   
There are cross-border military hotlines on both the east and west coasts, but Pyongyang severed the eastern line in 2011 after Seoul suspended tours to the North's Mount Kumgang following the shooting death of a South Korean tourist by a North Korean guard in 2008. (Yonhap News)