A senior No 10 aide has described in a tape-recorded interview how he was physically pushed aside by an angry Gordon Brown.
Stewart Wood, an Oxford don and senior foreign policy adviser to the Prime Minister, said that he had been left feeling “pretty shocked” by what had happened.
He said that No 10 staff used to apologise for the way Mr Brown behaved, saying “Oh that's just Gordon”.
However Mr Wood had increasingly come to see his conduct as an issue.
A version of the incident in which Mr Wood was brushed aside was recounted last week in a new book by the political journalist Andrew Rawnsley, The End of the Party.
Mr Rawnsley cited it as an example of the behaviour which, he said, had led Cabinet Secretary Sir Gus O'Donnell to give Mr Brown a “stern pep talk” about his treatment of staff — something No 10 denied.
Mr Brown himself strongly denied shoving or hitting people.
However, Mr Wood gave his own account of what happened in a tape-recorded interview with the author Suzie Mackenzie, who is writing an authorised biography of Mr Brown, which has been obtained by The Mail on Sunday.
In the interview Mr Wood said he was waiting for Mr Brown at the top of the stairs at No 10. “And... and he was in a really bad mood. And I leant forward and he went ‘Outta my way' and he did that (the paper said that he raised an arm in a strong, sweeping gesture imitating Mr Brown's action), ‘outta my way'. And then just walked in and then did it, smile on his face.”
In a statement, however, Mr Wood insisted that it was an isolated incident.