In 1997, Britain handed over Hong Kong back to China, this then was agreed that for 50 years after the deal was signed (1997) it would be a one country two systems policy. However, China is un-democratic and not respecting this agreement.
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New political parties and activist groups within Hong Kong have appeared recently with the British Hong Kong flag being taken to protests many times. The people are suffering and the 'so called' autonomous government even blocked a UK human rights activist from entering Hong Kong in October 2017. Also, a Hong Kong newspaper did a survey about Hong Kong independence and claimed that 92% voted they wanted to be British. The deal was supposed to stay in action until 2047 and is set in UN but no.