LIZ Truss has pulled out of a planned visit where she was due to face questions from journalists. 

The Prime Minister has given no reason for cancelling the trip on Wednesday to an electronics manufacturer in Hertfordshire specialising in defence, aerospace, transport and automotive technology.

Truss's official spokesman had said she would be hearing “from the kind of businesses driving UK innovation and growth”, but a little over an hour later the visit was cancelled due to “Government business”, according to a Downing Street source.

Earlier in a crunch PMQs - only her third since she moved into Number 10 - Truss said she was "completely committed" to the pensions triple lock despite new chancellor Jeremy Hunt ruling out agreeing to any further pledges, including the triple lock, ahead of the medium-term fiscal plan being announced on October 31.

It means pensions should rise in line with inflation, which hit 10.1% in September.

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There is speculation Sir Graham Brady, chair of the Tory backbench 1922 Committee, has already received more than 54 letters of no confidence in the PM - the threshold for triggering a vote if Truss was not still in the year-long grace period for new leaders.

William Wragg, the vice-chairman of the 1922 Committee, is the latest and sixth Tory MP to call for Truss to depart office, as he publicly announced he had filed a letter of no confidence.

He said: "What occurred with that financial statement- I am personally ashamed. I cannot go and face my constituents, look them in the eye and say they should support our great party."

The Downing Street source said the nature of the Government business behind the cancellation would become apparent later.