The former British defence minister has disputed that leaks came from him or his department - even though he was fired over it.
Gavin Williamson was sacked after an investigation into a leak from the UK's National Security Council.
A Downing Street spokesperson said Britain's Prime Minister Theresa May had "lost confidence in his ability to serve" in the cabinet.
They continued: "The prime minister's decision has been informed by his conduct surrounding an investigation into the circumstances of the unauthorised disclosure of information from a meeting of the National Security Council.
"The prime minister thanks all members of the National Security Council for their full cooperation and candour during the investigation and considers the matter closed."
File photo of former UK Defence Secretary Gavin Williamson and British Prime Minister Theresa May | Image: Daniel Leal-Olivas/PA Wire/PA ImagesIt marks the end of a probe into a leak from last week's meeting, which green-lighted a bid by Chinese telecoms giant Huawei to help build Britain's 5G network.
Details of the decision were leaked to the media, but there has been no official confirmation by the British government.
An internal investigation was launched with the possibility of a criminal inquiry.
Confirming the outcome on Tuesday, Downing Street said Mr Williamson had been fired over the "unauthorised disclosure".
In a letter to Mr Williamson, Mrs May said "the latest information from the investigation... provides compelling evidence suggesting your responsibility for the unauthorised disclosure.
"No other, credible version of events to explain this leak has been identified".
— Gavin Williamson (@GavinWilliamson) May 1, 2019
In his letter to Mrs May, Mr Williamson said: "I am sorry that you feel recent leaks from the National Security Council originated in my department.
"I emphatically believe this was not the case. I strenuously deny that I was in any way involved in this leak and I am confident that a thorough and formal inquiry would have vindicated my position."
Acknolwdging he was pushed from his position, he added: "I appreciate you offering me the option to resign, but to resign would have been to accept that I, my civil servants, my military advisers or my staff were responsible: this was not the case."
