In the Treaty of Nanjing in 1842, the Qing government agreed to make Hong Kong a colony of crowns after Britain`s victory in the First Opium War. In the second half of the 19th century, Britain had expressed concern about the security of the remote island of Hong Kong. Therefore, after Britain`s victory in the Second Opium War in the Beijing Congress, Britain obtained a permanent lease on the Kowloon Peninsula. The New Territories, with a 99-year lease, were the only areas forming the Hong Kong Crown Colony that had to be returned by mutual agreement. However, when serious negotiations took place in the 1980s, it was considered impractical to separate the surrendered territories and return only the new territories to China, due to the scarcity of resources in Hong Kong and Kowloon and major developments in the new territories. At midnight after the evening of June 30, 1997, the entire Hong Kong colony officially returned to Chinese sovereignty and ended 156 years of British rule. In 1997, the British handed Hong Kong over to China, the end of a 99-year lease and an event feared and awaited by the locals, the Chinese, the English and the rest of the world. Hong Kong has 426 square miles of territory in the South China Sea and is now one of the busiest and most economically independent parts of the world. This lease was born out of wars over trade imbalances, opium and the transfer of power of the British empire of Queen Victoria. Three years later, Deng received former British Prime Minister Edward Heath, sent as Special Envoy to Prime Minister Margaret Thatcher, to understand the People`s Republic of China`s plans for the handover of Hong Kong; During their meeting, Deng outlined his plan to make the territory a special economic zone that would retain its capitalist system under Chinese sovereignty.  The communist press published reports that the project was a bad plan to bleed comfortably in Hong Kong before handing over and leave the area in serious debt.  After three years of negotiations, Britain and the PRC finally agreed on the construction of the new airport and signed a Memorandum of Understanding.  To remove the hills and reclaim the land, it took only a few years to build the new airport.
The Executive Council made changes to the administrative policy and reviewed the primary legislation before handing it over to the Legislative Council for approval. This advisory body itself has also passed secondary laws as part of a limited series of colonial regulations. The Legislative Council reviewed the legislative proposals and was responsible for the use of public funds. This chamber was reformed in the last years of colonial rule to establish a more democratic representation.  Indirectly elected functional constituency seats were introduced in 1985 and geographic constituency seats elected by the popular vote in 1991. A new electoral reform in 1994 made the legislative power largely representative. The administrative public service was headed by the Colonial Secretary (later Chief) who was the deputy governor.  Formally, the answer is given to the second Beijing agreement, signed on 9 June 1898. The dilapidated Qing Dynasty leased the New Territories to Great Britain for 99 years from 1 July 1898. Newcomers are expected to make up 90% of Hong Kong`s land mass. The duration of 99 years was fixed almost incidentally.
Both sides believed that the new lands would remain British forever, with the original colonial ownership of Hong Kong Island acquired in 1842.