Government ministers call for a "full and proper" investigation after high-level discussions about Britain have leaked out with Huawei technology.
The government has approved the supply of equipment by the Chinese telecommunications company for the new 5G data network in the UK despite warnings of a security risk.
It is believed that the decision was made on Tuesday at a meeting of the National Security Council of the government.
One minister said leaving the Council was "simply unacceptable".
According to BBC political editor Laura Kuenssberg, the high-ranking minister said that licking talks was "extraordinary … the Security Council is the holy of holies".
The minister said that there had to be a "full and proper leak detection" where those responsible lost their jobs if necessary.
They added that they had "big concerns" because they wanted to "go to bed" with the telecoms giants.
Another minister said six of them would write down Downing Street asking for a full investigation, as well as number 10, to rethink the merits of the Chinese company's role.
There is no formal confirmation that Britain uses Huawei technology in its 5G networks. Huawei already supplies equipment for existing networks in the UK.
Number 10 said a final decision will be taken at the end of spring.
According to the Daily Telegraph, Huawei is allowed to help with the construction of the "non-core" parts of the 5G network like antennas.
Huawei has denied that his work poses any threat of espionage or sabotage or that it is controlled by the Chinese government.
But the US wants their allies in the "Five Eyes" newsgroup – Britain, Canada, Australia and New Zealand – to shut out the company.
In the past year, Australia has prevented its networks from using the Huawei 5G device.
Four ministers "against Huawei plan"
Prime Minister Theresa May led the weekly National Security Council meeting of the government on Tuesday, when the decision was made.
According to a political editor, one source said four Cabinet ministers opposed the idea and feared security could be compromised.
The source warned against allowing the company to participate, it was a mistake and a "question of the Prime Minister's verdict" and those who argued against the move had not given up yet.
Conservative backslider Sir Nicholas Soames said the investigation must be criminal and the leak will "cause our friends and allies to ask if we can be considered reliable – who is responsible should be turned down [from] the ministry of the queen ".
Regardless, the powerful Westminster News and Security Committee is expected to meet tomorrow to discuss the leak.
They should start a major investigation into China, including cybersecurity.
Leak by the Security Council is a different order
Regardless of the decision itself, which is still ongoing, the fact that the talks have leaked out is really upset.
The current Cabinet was memorably called the "worst in British political history" because the man who ironically should take over the discipline himself is the chief whip.
But a leak from the Security Council is a completely different order.
So, up to six ministers will probably turn to number 10 and complain, demanding a "full and proper" investigation of who disclosed the information.
Read more about Laura here.
What is 5G?
5G is the next (fifth) generation of mobile Internet connectivity that promises much faster data download and upload speeds, broader coverage, and more robust connectivity.
The world is getting mobile and the existing frequency bands are being overburdened, leading to failures, especially when many people in a region are simultaneously trying to access services.
5G is also much better at handling thousands of devices at the same time, from phones to device sensors, video cameras to smart street lights.
Current 4G mobile networks offer speeds of about 45 Mbps (megabits per second) on average, and experts say 5G, which will be launched in the UK this year, could surf and download up to 20 times faster.
- Read more about 5G
- Six cities in the UK were referred to as 5G pioneers