Top Gear presenter Jeremy Clarkson's contract will not be renewed, the BBC has announced.

Director-general Tony Hall said the decision had been taken with "great regret".

He said: "It is not a decision I have taken lightly."

Clarkson has been suspended from the hit motoring show since he was involved in what the BBC called a "fracas" with producer Oisin Tymon.

Mr Hall said he had met and spoken to both men and was publishing the findings of the BBC's internal investigation, though he added that he took "no pleasure" in doing so.

He said: "The BBC is a broad church. Our strength in many ways lies in that diversity. We need distinctive and different voices but they cannot come at any price. Common to all at the BBC have to be standards of decency and respect.

"I cannot condone what has happened on this occasion. A member of staff - who is a completely innocent party - took himself to Accident and Emergency after a physical altercation accompanied by sustained and prolonged verbal abuse of an extreme nature.

"For me a line has been crossed. There cannot be one rule for one and one rule for another dictated by either rank, or public relations and commercial considerations."

The BBC report said Mr Tymon, who "believed that he had lost his job" after the attack, drove himself to a "nearby A&E department for examination".

It added that Clarkson "made a number of attempts to apologise" to Mr Tymon "by way of text, email and in person".

Mr Tymon said he was "grateful" for the "thorough and swift investigation into this very regrettable incident".

He said: "I've worked on Top Gear for almost a decade, a programme I love. Over that time Jeremy and I had a positive and successful working relationship, making some landmark projects together. He is a unique talent and I am well aware that many will be sorry his involvement in the show should end in this way."

Paul Daniels, from law firm Slater Gordon which represents Mr Tymon, said the last month had "been a nightmare" for him.

He said: "He now simply wishes to return to the job he loves at the BBC. He does not intend to make any further media comment and kindly asks that his privacy is respected."