The New Yalu River Bridge that connects China’s Dandong and North Korea’s Sinuiju has yet to open to traffic. (Yoshikazu Hirai)

DANDONG, China--China has promised to foot the bill for the construction of related facilities for an already-completed bridge across the border between China and North Korea, sources said.

Chinese President Xi Jinping made the pledge when he visited North Korea in June, they said.

During the visit, Xi also promised that China will promote construction of an economic development zone on North Korea's Hwanggumpyong Island in the Yalu River, which forms a natural border between the two countries, the sources added.

Construction of the bridge and the economic development zone were agreed on when former North Korean leader Kim Jong Il was still alive. But the projects were effectively frozen after his son and successor Kim Jong Un became the country’s leader.

Xi’s willingness to pay the costs of building an access road to the bridge on the North Korean side of the border, as well as customs-related facilities, suggest that economic relations between the two neighbors are moving to a firmer footing.

According to sources knowledgeable about trade between the two countries and those with links to North Korean authorities, Xi’s promises were conveyed to high-ranking North Korean government officials during meetings to report on the outcome of a summit meeting between the two countries.

Xi's largesse was also shared in the North Korean military as it will be involved in the construction of bridge-related facilities as well as the economic development zone.

The New Yalu River Bridge connects Dandong in China with Sinuiju in North Korea. Although the bridge has been completed, it is not yet open to traffic.

China will provide about 2.5 billion yuan (39 billion yen, or $360 million) for the construction costs. Chinese engineers have been conducting field surveys since late June.

Since around that time, the upper parts of the bridge have been lit up at night.

In mid-July, cars carrying Chinese government officials traveled to a border gate in the middle of the bridge.

Construction of the bridge started in 2011 when Kim Jong Il was in power. China spent about 1.8 billion yuan in construction costs. The bridge was completed in 2014 under Kim Jong Un’s regime.

After its completion, North Korea asked China to bear the construction costs of related facilities. Since then, the bridge remained as it is without being opened to traffic.

Construction of the economic development zone in the Yalu River also started in 2011. However, Jang Song Thaek, the vice chairman of North Korea’s National Defense Commission who was acting as a go-between with China, was executed in late 2013.

Since then, the project remained idle.