Published7 minutes ago
Boris Johnson's adviser on the ministerial code has resigned after the PM backed Home Secretary Priti Patel over a bullying inquiry.
But Mr Johnson rejected Sir Alex's findings and said he had "full confidence" in Ms Patel.
Ms Patel released a statement saying she was sorry "that my behaviour in the past has upset people".
Ministers are normally expected to resign if they break the code and there are no known cases of a minister staying in post following a breach.
A government statement said Mr Johnson was "reassured that the home secretary is sorry for inadvertently upsetting those with whom she was working".
"He is also reassured that relationships, practices and culture in the Home Office are much improved," it said.
Sir Alex announced his resignation as the prime minister released his statement on the report's findings.
"I recognise that it is for the prime minister to make a judgement on whether actions by a minister amount to a breach of the ministerial code," he said.
"But I feel that it is right that I should now resign from my position as the prime minister's independent adviser on the code."
In his findings, Sir Alex said Ms Patel "has not consistently met the high standards required by the ministerial code of treating her civil servants with consideration and respect" and cited examples of "shouting and swearing".
He added: "Her approach on occasions has amounted to behaviour that can be described as bullying in terms of the impact felt by individuals.
"To that extent her behaviour has been in breach of the ministerial code, even if unintentionally."
However, he added that the home secretary had "legitimately - not always felt supported by the department".
"In addition, no feedback was given to the home secretary of the impact of her behaviour, which meant she was unaware of issues that she could otherwise have addressed."
In a statement, Ms Patel said "I am direct and have at times got frustrated", but added: "It has never been my intention to cause upset to anyone."
"I am sorry that my behaviour in the past has upset people," she said.
What is the ministerial code?
Responding to the news, Labour leader Sir Keir Starmer said: "Yet again, the prime minister has been found wanting when his leadership has been tested.
"If I were prime minister, the home secretary would have been removed from her job."
Lib Dem leader Sir Ed Davey said "Priti Patel has broken the ministerial code, the PM should have sacked her.
"He seems to believe there is one rule for him and his friends and another rule for everyone else - totally unacceptable."
The head of the civil servants' union FDA Dave Penman said: "What is the point of the investigation if actually what we're saying is it doesn't matter what evidence has been found, it doesn't matter what the PM's own adviser on the ministerial code says, if it's politically convenient for the PM to ignore it, he will ignore it.
"The PM in his forward to the ministerial code said there will be no bullying and no harassment, he didn't mean it, those words are hollow now."
The inquiry was launched by Boris Johnson in March, following the resignation of top civil servant at the Home Office Sir Philip Rutnam. Sir Philip - who is suing the government for constructive dismissal - alleged staff felt Ms Patel had "created fear".
Sir Alex Allan's report examined Ms Patel's behaviour at three different government departments - the Home Office, Work and Pensions and International Development.
Sir Keir has called for his report to be published in full but the Cabinet Office has insisted there is no full report, just a collection of evidence containing witness statements.