One of Somerset's MPs has called for prime minister Liz Truss to be replaced "as swiftly as is possible" to prevent further instability.

Mrs Truss resigned as prime minister on Thursday afternoon (October 20), becoming the shortest-serving prime minister in UK history – beating the previous record held by Tory premier George Canning, who ruled for 119 days before his death in 1827.

Sir Graham Brady MP, chairman of the 1922 Committee of backbench Conservative MPs, announced later the same day that Mrs Truss' successor would be in place by October 28 at the latest, with the first round of the leadership election expected to be held on Monday (October 24).

David Warburton MP – who will not be taking part in the vote after having the Tory whip removed in April – has urged the party to get this process over and done with quickly in order that the "significant challenges" facing the country can be tackled.

Mr Warburton was first elected as the Conservative MP for Somerton and Frome in 2015, having achieved the largest constituency swing in England at that year's general election.

He was suspended from the party in April following allegations of sexual harassment and cocaine use (which he strongly denies), and has been receiving treatment at a psychiatric hospital since July.

He said: "I very much respect and welcome Liz Truss's decision to resign.

"It's crucial we put in place a new leader and prime minister who truly has the strength of purpose that Britain needs.

"This is an extraordinarily testing time for the country so this process must be as swiftly as is possible.

"In Somerset we need stability now, and a clear understanding of what the government will do for us and how it will do it.

"I am pressing for the leadership contest to be conducted expeditiously and look forward to a new Prime Minister who will command both local and national support as we face the very significant challenges that must be overcome – and overcome rapidly."

Due to the Conservative whip being withdrawn, Mr Warburton will not be able to vote in the leadership election.

Councillor Sarah Dyke, the Liberal Democrats' parliamentary candidate for Somerton and Frome, called on the county's MPs to "do their patriotic duty" and demand a general election.

She said: "Boris Johnson failed our country and Liz Truss trashed our economy.

"People in Somerton and Frome deserve better than this incompetent and chaotic government, which has sent mortgages spiralling while our NHS services are stretched to breaking point.

"The Conservative Party has proven time and time again that it is not fit to lead our great country.

"This country needs a general election and local Conservative MPs in Somerset now need to do their patriotic duty. Conservative MPs cannot prop up more chaotic governments.

"At the next election, people across Somerset will be backing the Liberal Democrats to get a fair deal on the NHS and the cost of living, instead of more Conservative chaos."