China's detention of Yang Bin, a top Chinese-Dutch tycoon proves that the relationship between Beijing and Pyongyang is under severe stress, diplomatic sources said here on Sunday. Yang was recently appointed by North Korea to head its first special economic zone. Chinese police arrested Yang on October 4 in the north-east Chinese city of Shenyang but has not specified the charge against him. Reports, however, said he may have been detained for tax evasion in China. Washington will keep talking with N Korea TOKYO: US special envoy James Kelly headed back to the US on Sunday after briefing Japanese officials about talks with North Korean officials that he said were frank and useful. Kelly is Assistant Secretary of State for East Asian and Pacific Affairs. In the hour-long briefing, attended by Foreign Minister Yoriko Kawaguchi, Kelly said he had told N. Korean officials the US was concerned the secretive communist state’s conduct could have implications for regional and global security. (Reuters) Yang, 39 was appointed by North Korea as the first chief executive of the new Sinuiju Sez situated on the Chinese border. He is chairman of the Euro-Asia Agricultural (Holdings), which is listed in the Hong Kong Stock Exchange. ‘‘By arresting and detaining Yang, Beijing may be reminding Pyongyang that its economic policies and international relations should be developed under Chinese guidance,’’ a diplomat said. Interestingly, China had declined to comment on Yang’s appointment as the first chief executive of Sinuiju Sez, a rare honour bestowed by Pyongyang on a foreigner. ‘‘We have noticed North Korea’s announcement to set up Sinuiju special administrative region. We welcome and support this new step by North Korea in economic construction,’’ the Foreign Ministry spokesperson had said on September 24. Diplomatic sources said that for over a year, Pyongyang has been drifting away from Beijing as China’s international position has waned in the aftermath of the September 11 terror attacks. Realising this, North Korea has turned toward Russia. Beijing, however, wanted to retain its influence over Pyongyang and by taking such a drastic step like detaining Yang, the China has sent a clear signal to the world: China remains the Pyongyang gateway to the outside world, diplomatic sources said.