Shadow Cabinet of Margaret Thatcher Cabinet ceased to exist upon her becoming Prime Minister following the 1979 general election. Thatcher announced her first Shadow Cabinet on 18 February 1975. On 15 January 1976, Thatcher reshuffled the Shadow Cabinet. Pym returned as Shadow Agriculture Minister, displacing Jopling. George Younger was dropped from the front bench, and he was replaced by Gilmour at Defence; Whitelaw, the Deputy Leader, added Gilmour's Home Affairs portfolio to his Devolution. John Biffen replaced Jenkin as Shadow Energy Secretary, and Jenkin took Health from Fowler, who was demoted to be a Shadow Transport Minister (which was not in Shadow Cabinet and was
Third Thatcher ministry European Community. On 14 November, former cabinet minister Michael Heseltine challenged Thatcher's leadership. Thatcher polled higher than him in the first round of the leadership contest, but failed to gain an outright victory in the first round of voting. Within minutes of the result being announced, Thatcher informed reporters that she intended to let her name go forward for the second ballot. However, on 22 November, before a second round of the contest could take place, Margaret Thatcher announced her resignation as Prime Minister and Leader of the Conservative Party after more than 11 years, explaining that she was resigning