The United States has blocked a UN agency's efforts to improve civil aviation in North Korea at a time when Pyongyang is trying to reopen part of its airspace to foreign flights, according to three sources familiar with the matter.
The US move is part of a negotiating tactic to maintain sanctions pressure on North Korea ahead of a second summit between President Donald Trump and leader Kim Jong Un in Vietnam in February.
Washington is seeking concrete commitments from Pyongyang at the summit to abandon its nuclear and missile programs.
The United Nations' International Civil Aviation Organisation (ICAO), with 192 member countries, has been working with Pyongyang to open a new air route that would pass through North and South Korean airspace.
Airlines currently take indirect routings to avoid North Korea due to the threat of unannounced missile launches.
If the space was deemed safe, international airlines could save fuel and time on some routes between Asia and Europe and North America, and North Korea could begin reviving its commercial aviation industry.
The Montreal-based ICAO was prepared to help improve North Korea's aviation system by leading training sessions between its military and civil aviation staff, sources told Reuters, and North Korea asked for access to US-produced aeronautical charts.
But the United States discouraged the UN agency from helping North Korea with its air program as Washington wanted to "pool all the leverages and incentives" until Pyongyang makes substantial progress on denuclearisation.
ICAO cannot impose binding rules on governments, but wields clout through its safety and security standards which are approved by its member states.
Asked for comment, a US State Department official said it does not publicly discuss details of diplomatic conversations. An ICAO spokesman did not immediately respond to a request for comment.
The biggest beneficiaries of lifting air restrictions over North Korea would be South Korean carriers including Korean Air Lines and Asiana Airlines Inc.
