Sir Geoffrey Howe, deputy prime minister to Margaret Thatcher, resigned on 1 November 1990. His resignation speech on 13 November, a stinging rebuke of Thatcher's European policy, is thought to have been a catalyst to the prime minister's departure nine days later.
Howe drove the knife deep into divisions in the Conservative leadership, portraying Thatcher's attitudes to the European Monetary System as damaging for both country and party.
He is not generally regarded as a great orator -- indeed, Denis Healey once likened Howe's debating style to "being savaged by a dead sheep". Nonetheless, this statement to the Commons has entered the annals of momentous political speeches. It is seen as central to Michael Heseltine's race for leadership, and the vital first step towards reconciling that "tragic conflict of loyalties" which had driven Howe from the cabinet.
The tragedy is -- and it is for me personally, for my party, for our whole people, and for my Right Honourable Friend herself, a very real tragedy -- that the Prime Minister's perceived attitude towards Europe is running increasingly serious risks for the future of our nation. It risks minimising our influence and maximising our chances of being once again shut out.
I believe that both the Chancellor and the governor are cricketing enthusiasts, so I hope that there is no monopoly of cricketing metaphors. It is rather like sending your opening batsmen to the crease only for them to find, the moment the first balls are bowled, that their bats have been broken before the game by the team captain.
The Labour councillor and blogger Bob Piper says: "This speech, though lacking the oratory of Obama, King or Kennedy, was superbly crafted and hit its target right between the eyes. Two weeks later, she was gone. A joy to behold."
And the blogger Cath Elliott says: "Maybe it's not a great speech as far as speeches go, but it was certainly historic -- an event that a lot of people remember with great fondness."
Previous speech: Neil Kinnock, Militant speech, Labour party conference, October 1985