A former government national security adviser has warned that leaks from the National Security Council could undermine the willingness of senior civil servants and intelligence officials to speak freely to ministers about sensitive issues.
Sir Mark Lyall Grant, who was secretary to the NSC as the government’s top security official from September 2015 to April 2017, said this week’s leak of details from the committee was “extremely unusual”.
Earlier this week it was revealed that ministers had decided Chinese telecoms firm Huawei could provide some elements of the equipment for the UK's future 5G data network, despite warnings of a security risk. It is believed the decision was taken at a meeting of the government's National Security Council on Tuesday.
The leak has led to calls for an inquiry into how the information was made public. The Times reported that the leak had sparked anger among intelligence chiefs, with one source telling the paper the account of the meeting was "evidently briefed to make a leadership candidate look tough on China".
One minister told the BBC that the NSC was "the holy of holies", with the leaks branded "simply not acceptable", while Labour’s shadow Cabinet Office minister Jon Trickett said the NSC was being used “as political ammunition in a Tory party civil war”.
"The government should launch a full investigation to get to the bottom of these leaks, otherwise it risks further extinguishing what little authority it has left,” he said.
Speaking on the Today programme this morning, Lyall Grant said NSC members discuss particularly sensitive issues and therefore a leak was extremely unusual.
“Agendas are not publicised in advance, the outcomes of meetings are not publicised after the meetings and I can’t recall during the two years when I was doing the jobs any leaks from the National Security Council of this sort,” he said.
He highlighted that the committee's members, who include senior military and intelligence officials as well as civil servants and ministers, “need to be able to talk honestly and openly to help ministers to reach effective decisions and if it is going to leak like every other committee, that can be damaging in the longer term".
“The risk is that it undermines confidence of those who are paid to speak truth to power, to explain to minsters some of the underlying intelligence issues. That would be very damaging in principle. So I can fully understand the demands for there to be a leak inquiry, though that is obviously a decision for the prime minister [Theresa May] and the cabinet secretary [Sir Mark Sedwill, who is also national security adviser].”
Speaking in the Commons on Wednesday, Cabinet Office minister David Lidington insisted that no decision had yet been made on Huawei's involvement in the 5G network, and said findings from an ongoing government review would be released "in the proper way".
The United States, New Zealand and Australia have already barred the company from supplying some elements of their own telecoms infrastructure.
But Jerry Wang, chief executive of Huawei UK, said objections to the firm in the US were "not based on security concerns, but a barely concealed protectionist trade agenda". The company has long denied links to the Chinese state and pointed out that its technology is already used in the 4G network.
Additional reporting by Matt Foster