The UK's Intelligence and Security Committee (ISC) has said it will investigate Chinese firm Huawei in light of reports from the US earlier this week that cited major security concerns with the network giant.
At the start of the week the government told V3 it was not concerned by the reports by the US and stood by its own security procedures for vetting Huawei.
Now, though, according to The Guardian ISC chairman Malcolm Rifkind has revealed the committee will investigate the firm.
"We are looking into the relationship that has developed between Huawei and BT and the implications for the UK," he reportedly said.
"We wanted to look at the historical background to that contract, to what extent there were security concerns at the time, whether and to what extend the British government were involved in these decisions.
"And whether there have been any causes for concern that have arisen since Huawei became involved in our telecoms infrastructure."
V3 contacted the ISC for comment and clarification on its investigations but it declined to comment further.
Huawei stood by its position in the UK market and said it would help in any investigation if required.
‘We have been subject to UK government scrutiny and procedure since we opened our first office here in 2001," it said.
"We have regular contact with the UK government and welcome all discussions and questions."
BT stood by its relationship with Huawei and said it was confident its own security procedures are robust enough to protect its infrastructure.
"BT takes a risk-management approach on the use of components from Huawei and, like the UK government, we see no need to change our position following the US report," it said.
"BT's network is underpinned by robust security controls and built-in resilience. We always work closely with each of our suppliers - and government where appropriate - to gain assurance through rigorous review that the security of the network is not compromised."
The move by the ISC to launch an enquiry into the Chinese firm marks a turning point in the UK's attitude towards Huawei, which until now has been positive, with prime minister David Cameron even meeting chief executive Ren Zhengfei.
The firm is also the major partner to EE for its telecoms infrastructure in the UK, and is likely to be working with the firm at present on the rollout of 4G technology on its existing 2G network in the 1800MHz spectrum.
EE has also moved to defend its relationship with Huawei. Whether or not the investigation could have any impact on its 4G rollout remains to be seen.
V3 contacted EE to ask if there was any risk of a delay but it said it had no further comment to make.
Vodafone, which also uses Huawei equipment as well as ZTE, said it works with the firms to ensure the necessary security assurance.
"This includes continuous rigorous testing of all of our suppliers' network equipment," it added.
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