The joint declaration between the Chinese Undino-British was signed in Beijing on 19 December 1984 by the Prime Ministers of the People`s Republic of China and the governments of the United Kingdom. The declaration came into force on 27 May 1985 with the exchange of ratification instruments and was registered at the United Nations on 12 June 1985 by the People`s Republic of China and the governments of the United Kingdom. The enclave remained part of Chinese territory despite the tumultuous events of the early 20th century, which saw the fall of the Qing government, the creation of the Republic of China, and then a Chinese Communist government (PRC). Despite the finitude of the rental of the new territories, this part of the colony was developed just as quickly, and was very integrated with the rest of Hong Kong. As the lease drew to a close and pending serious negotiations on Hong Kong`s future status 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 land and natural resources on Hong Kong Island and Kowloon, significant infrastructure investments have been made in the New Territories, with break-evens well beyond June 30, 1997.  The signing of the joint declaration caused some controversy in Britain because British Prime Minister Margaret Thatcher agreed with the Chinese Communist government, represented by Deng Xiaoping.  In the White Paper containing the Joint Statement, Her Majesty`s Government stated that “the alternative to the adoption of this agreement is not to reach an agreement”, a statement that refuted criticism that the Declaration had made too many concessions to China and highlighted China`s considerable influence during the negotiations.  The 1898 convention, which for 99 years ceded other parts of Hong Kong (the New Territories) to Britain, excluded the Walled City, which has a population of about 700. It said that China could continue to maintain troops there until they interfered in Britain`s temporary rule. China disputes the practical effect of the declaration after the transfer of Hong Kong`s sovereignty, which said it was a “historical document that no longer had practical significance,” while the United Kingdom declared it a “legally valid treaty to which it felt obligated.”  Britain now believes that China has violated the joint declaration three times, including with the national security laws for Hong Kong introduced this year. The transfer of Hong Kong`s sovereignty (designated by the Chinese and British press respectively as “return” and “transfer”) took place as planned on 1 July 1997.
Since the return, only certain things have changed, such as the Hong Kong flag and the Prince of Wales Building, renamed the People`s Liberation Army Building. The mailboxes were painted green, as is customary in China. Street names have remained unchanged and the Royal Hong Kong Yacht Club has retained its “Royal” prefix, although the Hong Kong Jockey Club and other institutions have abandoned the title.  On 19 December 1984, after years of negotiations, the British and Chinese leaders signed a formal pact authorizing the colony`s turnover in 1997, in exchange for formulating a Chinese Communist government policy with a “one country, two systems”.