North Korea has stopped transmitting signals which jammed the GPS systems of hundreds of civilian aircraft and ships in South Korea for two weeks, officials said Tuesday.

The state Korea Communications Commission said the signals designed to jam global positioning systems halted as of 8:34pm on Sunday.

The transport ministry confirmed civilian flights had not been affected since Sunday night.

South Korean officials said the signals originated from the North’s border city of Kaesong and began on April 28, forcing sea and air traffic to use other navigational equipment to avoid compromising safety.

The reason for the jamming, which the North has not admitted, was unclear but it came at a time of high cross-border tensions.

The North has threatened “sacred war” against the South in retaliation for perceived insults during Pyongyang’s commemoration in April of the centenary of the birth of founding leader Kim Il-sung.

The North has twice before been accused by Seoul of jamming GPS systems but there was no previous widespread effect on civilian flights.

The latest exercise may have been intended to “test electronic warfare devices by the North Korean military or block mobile phone signals inside the North”, said a South Korean military official quoted by Yonhap news agency. (AFP)