Details from the highly secretive National Security Council emerged in the press on Wednesday, a day after a meeting at which Theresa May and senior ministers discussed the issue with chiefs of security and intelligence agencies.
Reports suggested top spies and government ministers were also furious at the unprecedented leak from a forum at which sensitive matters are discussed openly in confidence that they will not be shared more widely.
Conservative grandee Sir Nicholas Soames told the BBC that the leak would “cause our friends and allies to wonder if we can be considered reliable” and called for those responsible to be sacked.
Labour’s shadow Cabinet Office minister Jon Trickett said: “This Tory government has once again proved incapable of coming together to protect the public interest.
“Critical issues of national security should be handled with utmost care, not 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.”
It is understood that the NSC meeting agreed that Huawei could be given work on “non-core” elements of the 5G network, despite misgivings voiced by ministers including Jeremy Hunt, Sajid Javid, Gavin Williamson and Penny Mordaunt.
The US has barred Huawei from involvement in official networks and put pressure on its Five Eyes intelligence partners to do the same over security concerns surrounding the company’s links with the Chinese government.
Rob Joyce, a senior adviser at the US National Security Agency, said that Washington did not want to hand Beijing a “loaded gun” and would be looking closely at the UK decision.
He told the Financial Times: “We have got to understand all the details of that and decide what that means.
“What we will be insistent on is UK decisions can’t put our information at risk but the good news is that the UK already understands that.”
Mrs May’s effective deputy David Lidington told MPs that no decision had been made on Huawei’s involvement in 5G.
He said a government review was looking at creating “greater resilience and critically diversity in the entire supply chain”, adding that when decisions were made “we will announce them to the House in the proper way”.
But he stressed that “legally speaking [Huawei] is a private company not a government-owned company”.
And the director of the GCHQ eavesdropping agency appeared to seek to calm nerves over Chinese involvement in the 5G network, saying that technical issues were more important than “flag of origin”.
Jeremy Fleming told the Cyber UK conference in Glasgow: “A flag of origin of 5G equipment is important but it is a secondary factor.
“It’s a hugely complex strategic challenge, going to span the next few decades. How we deal with it will be crucial for our prosperity and for our security.”
Cabinet minister Liz Truss said Huawei involvement should not be ruled out, telling the BBC: “We need to decide on a case-by-case basis based on the security advice, but that should be led by the UK – we shouldn’t be deciding on the basis of what the Americans think or what the Australians think.”
Ciaran Martin, head of GCHQ’s National Cyber Security Centre, told BBC Radio 4’s Today programme that the review was “about the fundamentals of how to keep these networks safe from any attacker” and not just Huawei.
“Some of the 5G infrastructure is built over existing networks so it’s not as if we are completely reinventing the wheel here,” he added.
“We’ve set out that objective independent technical assessment of what’s needed and I’m confident ministers will reach a decision that will provide for the type of safer 5G networks that we need.”
A Downing Street spokeswoman said: “We don’t comment on NSC discussions.”
The reported decision came after a number of senior security figures warned publicly of the risks involved in allowing a Chinese firm access to the UK’s critical communications network.
MI6 chief Alex Younger has said Britain needs to decide how “comfortable” it is in allowing Chinese firms to become involved, while Mr Fleming, has spoken of both “opportunities and threats”.
Some critics have expressed concerns that the Chinese government could require the firm to install technological “back doors” to enable it to spy on or disable Britain’s communications network.
Last month, a government-led committee set up to vet Huawei’s products said it had found “significant technological issues” with its engineering processes posing new risks to the UK network.
Huawei has denied having ties to the Chinese government, but critics question how independent any large Chinese company can be, with a legal obligation on firms to co-operate with the state’s intelligence agencies.
Join our new commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies