Gavin Williamson, sacked as Britain's Defence Secretary by Prime Minister Theresa May for allegedly disclosing plans to allow Chinese telecommunication giant Huawei to help build the UK's 5G network, has denied leaking any information from the National Security Council.
His comments have come amid calls for a police inquiry into it. Opposition MPs say there should be an investigation whether the Official Secrets Act had been breached, the BBC reported.
Williamson was quoted in several newspapers on Thursday as saying he was the victim of a "vendetta" and a "kangaroo court". He told Sky News he "swore on his children's lives" that he was not responsible for the leak.
He also posted a letter on his Twitter account on Wednesday "strenuously" denying that he was the source of the leak.
Downing Street, however, said it had "compelling evidence" and the matter was closed.
The inquiry into the leak began after the Daily Telegraph reported on the National Security Council's confidential discussions, including warnings from several Cabinet members about possible risks to national security over a deal with Huawei.
At a meeting with Williamson on Wednesday, May told him she had information that suggested that he was responsible for the unauthorised disclosure. In a letter confirming his dismissal, she said: "No other credible version of events to explain this leak has been identified."
In response, Williamson, Defence Secretary since 2017, wrote he was "confident" that a "thorough and formal inquiry" would have "vindicated" his position. "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," he said.
Labour Party's deputy leader Tom Watson told BBC Radio 4's Today programme Williamson had "a right to clear his name" and the best way to do that was through a criminal inquiry. "This is about the law applying equally to everyone. We have had very high profile civil servants going to jail for breaching the Official Secrets Act," he said.
Disclosure of official information relating to security and intelligence by a "Crown servant", including government ministers, is illegal. Being found guilty of this carries a sentence ranging from a fine to two years in prison.