Contact between North Korea and outside world at the truce village of Panmunjom has been decreasing over the past two decades, partly due to the regime changes in the communist country, an official at United States Forces Korea said Sunday.

"After Kim Il-sung died, we saw the number of contacts we had at Panmunjom (with North Koreans) be reduced, and after the summit in 2000, we saw it reduced even more," said Stephen Tharp, Chief of Strategic Outreach of the USFK, told Yonhap News Agency.

"And these days, the contacts at Panmunjom have been greatly reduced. It's part of the regime change," he said, without further elaboration.

Upon the death of the North's founding father Kim Il-sung in 1994, his son Jong-il took the helm of the communist country. The younger Kim then led the country until his son, current leader Jong-un, succeeded power when he died in 2011.

Inter-Korean ties have ebbed and flowed over the years though the two Koreas have held summit meetings twice under the Kim Jong-il regime, one in 2000 with South Korea's then President Kim

Dae-jung and the other in 2008 with Roh Moo-hyun.

His assessment was based upon his years of service in the Demilitarized Zone bisecting the Koreas, including being the assistant secretary on the United Nations Command Military Armistice Commission. His firsthand experiences there led him to publish the book titled, "The Western DMZ Paju."

"I could have many chances to take charge of guard post inspections, Armistice violation investigations and meetings with the North Korean military representatives to discuss armistice-related issues," he said. "These experiences gave me valuable insights into the origins of the DMZ and the actual practices in effect today."

Saying it its "unfortunate" that the separation of the two Koreas is not fixed peacefully, Tharp stressed the DMZ is "the best place for both Koreans and foreigners to get a practical lesson regarding the security situation in Korea."

"The purpose of the book is to educate everyone on how to go to the DMZ ... We have to educate the young people about the realities of North Korea and the security situation here," he said.

As the first of his planned five-volume work on the Korean frontline, the book carries information on different sites along the border with North Korea where civilians are permitted to visit, including how to get there.

Stressing that the zone is not just the North Korean military but a place where people can learn "about diverse issues including the inter-Korean relationship and the lifestyle in the North," the Korea specialist expressed hope that his book would "serve as a guide for families to visit the DMZ and parents can teach their children."

Tharp has served more than 25 years in South Korea as both an active duty soldier and a Department of the Army civilian, and has been married to a Korean woman for 35 years, who helped him "understand a little bit of 'Han' (deep resentment) of the Koreans." (Yonhap)