The chief whip Andrew Mitchell has issued this statement after confronting police in Downing Street:
On Wednesday night I attempted to leave Downing Street via the main gate, something I have been allowed to do many times before.
I was told that I was not allowed to leave that way.
While I do not accept that I used any of the words that have been reported, I accept I did not treat the police with the respect they deserve.
I have seen the supervising Sergeant and apologised, and will also apologise to the police officer involved.
David Cameron admits it 'became apparent' to the former Chief Whip that he could no longer do his job. So why was it not apparent to the PM?
Government Chief Whip Andrew Mitchell has resigned after swearing at police guarding Downing Street.
Losing one's temper with a police officer would be excusable in most people, but for the Tory chief whip to do means so much more.