Hong Kong–United Kingdom relations a deeply important role in the formation of the modern Hong Kong. Sovereignty of Hong Kong was ceded to the UK "in perpetuity" on 29 August 1842 through the Treaty of Nanking. The UK further expanded the territory of Hong Kong in 1860 by another cessation, plus a 99-year lease of the New Territories in 1898. The stability, security, and predictability of British law and government enabled Hong Kong to flourish as a centre for international trade. Localisation of teritary institutions, the Hong Kong government and the independent Judiciary in the run-up to the 1997 Handover of sovereignty, caused a
Handover of Hong Kong room for compromise on the question of sovereignty over Hong Kong; the PRC, as the successor of Qing dynasty and the Republic of China on the mainland, would recover the entirety of the New Territories, Kowloon and Hong Kong Island. China considered treaties about Hong Kong as unequal and ultimately refused to accept any outcome that would indicate permanent loss of sovereignty over Hong Kong's area, whatever wording the former treaties had. During talks with Thatcher, China planned to invade and seize Hong Kong if the negotiations set off unrest in the colony. Thatcher later said that Deng told her