In 1956, members of the Legislative Assembly held constitutional talks with the Colonial Office in London. The talks broke down as Marshall did not agree to the British Government's proposal for the casting vote on a proposed Defence Council to be held by the British High Commissioner to Singapore, who would only exercise it in an emergency. Marshall resigned as Chief Minister in June 1956, and was replaced by Lim Yew Hock. The following year, Lim led another delegation to the UK for further talks on self-government. This time, agreement was reached on the composition of an Internal Security Council. Other constitutional arrangements were swiftly settled in 1958, and on 1 August the Parliament of the United Kingdom passed the State of Singapore Act 1958, granting the colony full internal self-government. Under Singapore's new constitution which came into force on 3 June 1959, the Governor was replaced by the Yang di-Pertuan Negara (Head of State), who had power to appoint as Prime Minister the person most likely to command the authority of the Legislative Assembly, and other Ministers of the Cabinet on the Prime Minister's advice. The Constitution also created the post of the British High Commissioner, who was entitled to receive the agenda of each Cabinet meeting and to see all Cabinet papers. In the 1959 general elections, the People's Action Party (PAP) swept to power with 43 out of the 51 seats in the Assembly, and Lee Kuan Yew became the first Prime Minister of Singapore. Nine other Ministers were appointed to the Cabinet.