In a long-awaited decision on Friday, the government declined a request by Google to use official Korean map data for its Maps app. A government committee had been reviewing the matter for five months.
National Geographic Information Institute chief Choe Byong-nam said the maps would identify secret installations that are usually left off maps for public use.
"Google's request for mapping data carries the risk of worsening the security threat from North Korea," Choe said. He added the government offered to provide mapping data by blurring out satellite images of classified sites, but the U.S. tech giant refused.
The decision was expected in August, but the government delayed the announcement by two more months to hold further negotiations with Google.
Choe said Seoul's decision placed top priority on national security but the government could consider further talks with Google.
"Security problems change over time," he said. "We can't say for sure that we would reject further requests by Google or other global business for mapping data."
Google was unhappy with the decision. "We're disappointed," Google spokesman Taj Meadows said in a statement. "We've always taken security concerns very seriously and will continue to provide useful map services in compliance with Korea's current map data export regulation."