Alan Milburn directly intervened in the performance ratings of a hospital in Tony Blair's constituency because it was "high profile", according to leaked documents.

Three days before the deadline by which the ratings had to be decided, the then-health secretary asked why the three-star South Durham Healthcare Trust was to be demoted to two stars.

A day later the ratings were recalculated and South Durham was again awarded three stars, making it eligible for a £1 million capital funding grant.

Last night Milburn vehemently denied any wrongdoing. "There is a very big difference between asking a question and giving an instruction," he said. "Absolutely no instruction was given."