Writing in The Sunday Telegraph, she attributed the party's worst-ever defeat - in which it was reduced to just 121 seats - to the party pursuing an "idiotic strategy of intermittently and inconsistently making 'Tory Right' noises which disintegrated when set against our liberal Conservative record".

"I say again, whatever some of my colleagues think, the voters aren't mugs: they saw what we did in office and ignored what we insincerely said while campaigning," she added.

The former home secretary - who retained her seat of Fareham and Waterlooville but with a much-reduced majority - blamed "high taxes" and "high immigration" as well as "insane political correctness" she believed the party had embraced for the scale of the defeat.