The director general of the BBC today defended the corporation's impartiality after it was disclosed he met a senior government aide in Downing Street to discuss coverage of the Government's spending cuts.
Mark Thompson insisted his meeting did not affect the BBC's "independence or impartiality in any way".
He had meetings "from time to time" with politicians and officials of all parties regarding coverage, and that was the "unremarkable context" in which his meeting with Mr Cameron's strategy chief Steve Hilton should be seen, he said.
He was responding to shadow culture secretary Ben Bradshaw who had called for "clarity and reassurance" after Mr Thompson was photographed arriving at Number 10 holding a memo from his head of news, Helen Boaden.
The memo disclosed she had previously met Downing Street director of communications Andy Coulson for lunch at which he was "concerned" the BBC should give "context" to its coverage of the forthcoming comprehensive spending review.
Mr Bradshaw wrote to Mr Thompson, saying: "Given the systematic assaults on the BBC by the Conservative Party in opposition and their continued attacks on the Corporation in Government, including their threats to the licence fee, I am sure you will agree that it is paramount that you avoid any impression that the BBC's editorial independence may have been compromised."
He said Mr Thompson should consider releasing the briefing papers he was seen holding as he walked into No 10.
In his letter Mr Bradshaw asked who requested the meeting, the BBC or Downing Street.
He asked if similar meetings had taken place with Gordon Brown or his staff and whether there had been other talks between BBC editors and No 10 political staff.
Mr Thompson released his reply to Mr Bradshaw in which he assured the shadow culture secretary: "I'm happy to assure you that nothing about this meeting - the fact of it occurring, its timing or the matters which were discussed - could be construed as compromising the BBC's independence or impartiality in any way."
He went on: "My role as editor-in-chief of the BBC means that from time to time I meet politicians and officials connected with all major parties to discuss our coverage.
"In answer to your question, I have had meetings with the leaders of all the UK's major parties.
"That is the unremarkable context in which yesterday's meeting should be seen.
"It had been arranged some months ago by mutual consent and was not unusual in any respect."