The Trump administration is keeping the heat up on the UK to freeze out Huawei, weeks after the UK announced it would allow Huawei to participate in building its 5G network.
During a speech at the Oxford Union on Wednesday, acting chief of White House staff Mick Mulvaney said the US is "very much concerned" about the decision per the Guardian.
"Our governments share a tremendous amount of security information," Mulvaney told the audience. "We are very much concerned that integrity of that information is hardwired into your computer systems, and if you folks go forward with the decision to include Huawei, it will have a direct and dramatic impact on our ability to share information with you. Period, end of story," he added.
Mulvaney made these comments one day before a scheduled meeting with Dominic Cummings, Boris Johnson's top aide.
The Trump administration has spent the last year furiously lobbying its allies to exclude Huawei from their 5G infrastructure, as it claims the Chinese tech company acts as a proxy for the Chinese government to spy. Huawei has repeatedly denied this, and claims the US' pursuit of the company is politically motivated.
Britain's decision last month to allow Huawei to build "non-core" parts of its 5G was a blow to the US, but initially Secretary of State Mike Pompeo said the US and the UK would continue to share intelligence, despite earlier threats that the US would have to cut ties with any country that allowed Huawei into its 5G.
Mulvaney's visit to the UK also comes a week after the US accused Huawei of spying telecoms backdoors designed for use by law enforcement. Earlier this week the US ambassador to Germany tweeted he had received a phone call from President Trump, reminding him that: "any nation who chooses to use an untrustworthy 5G vendor will jeopardize our ability to share intelligence and information at the highest level."
