A man reacts after catching a trout with his hands during an event promoting the Ice Festival on a frozen river in Hwacheon, about 20 km (12 miles) south of the demilitarized zone separating the two Koreas, January 10, 2015. The annual ice festival, which is one of the most famous and biggest festivals in South Korea, expects to see more than 1,000,000 people attend. The festival lasts for three weeks from January 10 this year. (Photo by Kim Hong-Ji/Reuters)

Models painted in camouflage colours to blend in with the background pose for Chinese artist Liu Bolin's artwork “Dongji”, or Winter Solstice, on the second day after China's capital Beijing issued its second ever “red alert” for air pollution, in Beijing, China, December 20, 2015. In this artwork, Liu wants to express his concerns about China and its people, including air pollution problem, Liu told Reuters. (Photo by Kim Kyung-Hoon/Reuters)

North Korean commuters are seen through a door window waiting to board a train in a subway train station in Pyongyang, North Korea, 14 April 2017. North Koreans are preparing to celebrate the “Day of the Sun” festival, commemorating the 105th birthday anniversary of former supreme leader Kim Il-sung on 15 April, as tension over nuclear issues rise in the region. (Photo by How Hwee Young/EPA)

Members of Japan's idol group “Virtual Currency Girls” wearing cryptocurrency-themed masks perform in their debut stage in Tokyo, Japan, January 12, 2018. Japanese female idols have teamed up to form the ‘Virtual Currency Girls’ group to promote the knowledge of cryptocurrencies through entertainment. Each of its 8 members represents a cryptocurrency: bitcoin cash, bitcoin, ether, neo, nem, ripple, mona, and cardano. (Photo by Kim Kyung-Hoon/Reuters)

Director Taro Kambe directs as he watches acting with VR headset during a rehearsal for ROCKET's 3D virtual reality adult film at the company's studio in Tokyo, Japan, July 31, 2017. Japan is the world's second biggest virtual reality market after the United States and the adult entertainment industry and gaming sector are turning to VR as a new way to distribute content. (Photo by Kim Kyung-Hoon/Reuters)

In a photo taken on July 29, 2018 instructor Kim Ju Yang (20) holds a North Korean- made assault rifle as she poses for a portrait at the Meari shooting range in Pyongyang. The Meari shooting range offers customers the opportunity to shoot a number of North Korean and foreign- made firearms, most of which have been modifed to fire .22 calibre ammunition costing one US dollar per round. (Photo by Ed Jones/AFP Photo)

Sakakibara Kikai's engineer Go Sakakibara poses with the bipedal robot Mononofu during its demonstration at its factory in Shinto Village, Gunma Prefecture, Japan on April 12, 2018. Developed at Sakakibara Kikai, a maker of farming machinery, LW-Mononofu is a 28-feet tall, two-legged robot weighing in at more than 7 tonnes. It contains a cockpit with monitors and levers for the pilot to control the robot's arms and legs. (Photo by Kim Kyung-Hoon/Reuters)

North Korean leader Kim Jong Un, his wife Ri Sol Ju and Song Tao, head of the International Department of Communist Party of China (CPC) Central Committee, applaud with ballet dancers in this undated photo released by North Korea's Korean Central News Agency (KCNA) in Pyongyang April 17, 2018. (Photo by Reuters/KCNA)