Chinese tech firm Huawei has branded US warnings to the UK over using the company's 5G equipment as "unsubstantiated allegations".
Huawei equipment could be used in some "non-core" parts of the network it has been reported previously, with a final decision due later in January.
Boris Johnson today hinted he was still open to working with the business on such infrastructure, stating those opposing it need to suggest alternatives.
In a statement this afternoon, Huawei's vice president Victor Zhang said: "We are confident that the UK Government will make a decision based upon evidence, as opposed to unsubstantiated allegations."
He also referenced MI5 suggestions that intelligence sharing between the US and UK would not be harmed by the use of the equipment.
Speaking this morning, Mr Johnson said: "The British public deserve to have access to the best possible technology.
"I have talked about infrastructure and technology. We want to put in gigabit broadband for everybody.
"Now, if people oppose one brand or another, then they have to tell us which is the alternative.
"On the other hand, let's be clear, I don't, as the UK Prime Minister, want to put in any infrastructure that is going to prejudice our national security or our ability to co-operate with Five Eyes intelligence."
It comes following Tory MP Bob Seely's call for the Foreign Affairs Committee to open an immediate investigation into Huawei's suitability for use in Britain's 5G network.
Bob Seely said Huawei "to all intents and purposes is part of the Chinese state" and its involvement would "effectively to allow China and its agencies access to our network"
Foreign Office minister Andrew Stephenson said a final decision will be "taken in due course".