London: China will not "sit by and watch" and is ready to "quell the unrest swiftly" if the crisis in Hong Kong becomes "uncontrollable", China's ambassador to London said on Thursday. "If the situation deteriorates further into unrest uncontrollable by the SAR (Special Administrative Region) government, then the central government will not sit by and watch," Liu Xiaoming said in a televised press conference.

"We have enough solutions and enough power to quell the unrest swiftly," he said. Images taken by AFP earlier on Thursday showed thousands of Chinese military personnel waving red flags and parading at a sports stadium in the city of Shenzhen, just across the border from Hong Kong. Dozens of armoured personnel carriers and supply trucks were also parked nearby. "We hope this will end in an orderly way. In the meantime we are fully prepared for the worst," Liu said. He also protested against "foreign interference" in the Hong Kong protests and urged British Prime Minister Boris Johnson's government to handle the issue with "great caution".