Perched just inside China, across a picturesque bend in the Tumen River and the North Korean border, sit 1.5 square kilometres of sleek new warehouses, containers and loading docks belonging to Hunchun Posco Hyundai Logistics International. With $100m invested so far, the joint venture, uniting three South Korean industrial conglomerates, is a massive bet on warming relations between China and North Korea.

It sits mostly idle these days, said the facility’s South Korean general manager Oh Jong-soo, with just 10 of 26 planned warehouses operating, and those are at 37 per cent capacity.

He glumly recounts the optimism that prevailed in the Chinese border region following the diplomatic opening to  North Korea by the US, South Korean and Chinese leaders over the past two months. But trade across the border, which was brought to a halt by UN  sanctions  last year, is at a standstill. He said sanctions last August deprived his company of handling 5,000 tonnes of seafood exports from North Korea.