It comes after ministers attacked the “outrageous” leak that the National Security Council (NSC) had approved Huawei’s bid to help build Britain’s 5G network.
Jeremy Wright told the Commons: “We cannot exclude the possibility of a criminal investigation”, adding that the issue “is serious and… the government intends to treat it seriously”.
Labour is demanding a full investigation into the leak, which has reportedly caused concern within the secret services, while Tory MP Nicholas Soames – grandson of Sir Winston Churchill – has called for a criminal inquiry.
When asked if she would be launching a formal inquiry, Prime Minister Theresa May said: “We don’t comment on leaks and on those matters.
“On the overall matter of security and our telecoms network, we are very clear that we give that high priority.
“We want to ensure we see greater resilience in our telecoms network and that we are able to provide high levels of cyber security, but we also see diversity of suppliers.”
The details were revealed in The Telegraph on Wednesday, along with a list of cabinet ministers who raised concerns about the idea.
One minister told Sky News a leak of that nature had “never happened before”.
A senior source pointed the finger of blame at the Ministry of Defence, adding that the “culprit… might be chopped”.
But Defence Secretary Gavin Williamson said: “Neither I nor any of my team have divulged information from the National Security Council.”
Foreign Secretary Jeremy Hunt denounced the leak as “utterly appalling” and added: “I have never leaked confidential Cabinet discussions and I never will, so I don’t want to comment further on it.”
Sajid Javid, the home secretary, said it is “completely unacceptable” for any minister to “share sensitive information that cannot be out in the public domain” and if it happens it should “absolutely be looked at.”
Health Secretary Matt Hancock told Sky News he understood Britain’s top civil servant was weighing up the idea of an official investigation.
Former defence secretary Sir Michael Fallon, who used to sit on the NSC, also told Sky News the police should be called in to track down the culprit behind the “completely unprecedented” action.
The NSC meeting on Tuesday saw Huawei granted restricted access to build “non-core” infrastructure such as antennas, Whitehall sources confirmed.
But the firm will be blocked from involvement in the most sensitive areas of the network.
Other members of the Five Eyes intelligence-sharing group, which includes the US, Canada, Australia and New Zealand, have already reaised concerns.
The US and Australia have barred Huawei from supplying key elements of their infrastructure, while New Zealand and Canada are still considering the matter.
Huawei denies having ties to the Chinese government.
But with a legal obligation to cooperate with the state’s intelligence agencies, critics worry that no Chinese company can ever be truly independent.
There are also concerns that the Chinese government could require the firm to install technological “back doors” to enable it spy on or disable Britain’s communications network.
Decisions of the NSC are taken collectively, but it was reported that concerns were raised during Tuesday’s meeting by a number of ministers.
They included Home Secretary Sajid Javid, Foreign Secretary Jeremy Hunt, Defence Secretary Gavin Williamson, International Trade Secretary Liam Fox and International Development Secretary Penny Mordaunt.
Author: Aubrey Allegretti and Alan McGuinness