 They initially supported the British Conservative Prime Minister Margaret Thatcher's efforts in insisting the validity of the Treaty of Nanking of 1842.However, Deng Xiaoping, the Chinese paramount leader insisted in restoring sovereignty in Hong Kong in 1997, but guaranteed the "capitalist system and way of life shall remain unchanged for 50 years," which was later written in the Article 5 of the Hong Kong Basic Law.Besides its "Old Left" Beijing loyalists in the colony which were represented by the Hong Kong Federation of Trade Unions (HKFTU), the Communist authorities in Beijing also actively ally with the business elites, professionals and rural leaders, who were used to be seen as pro-Nationalists, as part of their united front strategy.