There was a plot to oust the then Ulster Unionist leader, James Molyneaux, in 1982, according to newly-released confidential files.
In January 1982, Frank Millar, the Ulster Unionist press officer, told Northern Ireland Office officials morale in the party was low.
Its image among Protestants, especially in Belfast, was "disastrous", he said.
Millar said that the party was "all over the place" under Mr Molyneaux's leadership.
However, Mr Millar added that: "Everyone was terrified at the electoral implications of a public struggle to oust him."
On 3 February, 1982 Stephen Leach, an NIO official, recorded a conversation with Captain Austin Ardill, the convenor of the Unionist Devolution Group (UDG), a UUP pressure group which supported the restoration of devolved institutions.
Ardill told the official that there was "a wide consensus… that Molyneaux ought to be replaced as leader as soon as possible".
In his view, the Armagh MP, Harold McCusker was clearly the front runner.
In Mr Ardill's view 'the next step must be to secure Molyneaux's resignation'.
The UDG was planning an early approach to the UUP president, Sir George Clark. He believed that Mr Clark now thought the UUP leader should step down but wished that the manner of his going should not damage the party.
The plot failed and Mr Molyneaux was to remain UUP leader until 1995.