Update (0950ET): Sources on both sides have confirmed that the spat won't have any impact on the US-UK trade agreement that Trump and Johnson have touted.

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When Prime Minister Boris Johnson decided to defy the Pentagon's warnings and approve Huawei's bid to build "non-core" components of the UK's 5G network, the White House quickly made its dissatisfaction known, as we reported at the time.

Johnson was walking a fine line between appeasing the US and China. But as one observer remarked at the time, "you can't be half pregnant." A report published Friday in the FT seems to have confirmed this sentiment by revealing that President Trump lashed out at Johnson, a leader whom he had one lavished with praise, in a phone call held shortly after the announcement.

During a phone call held last week shortly after Johnson's decision was publicized, an aide said Trump was "apoplectic" with rage, and laid into Johnson using language that left many on the call completely dumbfounded.

A second official confirmed that the Trump-Johnson call was "very difficult." British officials with knowledge of the exchange said they were taken aback by the force of the president’s language towards Mr Johnson. Mike Pence, US vice-president, said after the Huawei decision that the Trump administration had made its disappointment at the UK decision "very clear to them." But the extent of Mr Trump’s anger was unknown until now. Downing Street, the US state department, the US National Security Council and the White House declined to comment on the call.

After the call, the White House released only a brief readout: "Today, President Donald J Trump spoke with Prime Minister Boris Johnson of the United Kingdom. The two leaders discussed critical regional and bilateral issues, including telecommunications security."

Downing Street's readout hinted at the tensions: "The prime minister underlined the importance of like-minded countries working together to diversify the market and break the dominance of a small number of companies."

Privately, the British chafed at the US's demands, particularly since the US didn't have a superior product to offer to replace Huawei.

Sensing this, AG William Barr went so far as to suggest that the US buy stakes in Ericsson and Nokia, the two Scandinavia telecoms components giants, to allow the US to have something to offer its allies instead of just asking them to go without Huawei's cutting-edge telecoms equipment for their 5G rollouts.

Mr Barr said America and its allies should be "actively considering" proposals for "American ownership of a controlling stake" in the European companies, “either directly or through a consortium of private American and allied companies”. He added "it’s all very well to tell our friends and allies they shouldn’t install Huawei’s, but whose infrastructure are they going to install?"

The two sides left reporters with distinctly different impressions about the condition of their relationship. The US reportedly insisted that the White House spent considerable time and resources trying to convince Johnson to abandon Huawei. However, Downing Street said President Trump's strident views on Huawei were barely known to the administration before the phone call. Though Washington approved some sales to Huawei last year, Trump apparently still believes the company is "very dangerous."

U.S. Attorney General William Barr said the United States and its allies should consider taking a ‘controlling stake’ in Finland’s Nokia and Sweden’s Ericsson to counter China-based Huawei’s dominance https://t.co/Enl3yL0cxV pic.twitter.com/n77yN2ztK1 — Reuters (@Reuters) February 7, 2020

As one academic who spoke with the FT for its story about the rift pointed out, the UK's decision to buy some equipment from Huawei could compromise the 'Five Eyes' intelligence alliance between the US, UK, Canada, Australia and New Zealand. Though Secretary of State Mike Pompeo has apparently made some progress in repairing the relationship during a recent visit to the UK - "friends don't always agree on everything" - he also insisted that the US would take steps to ensure the security of the alliance.

Has China succeeded in driving a wedge between President Trump and one of his most natural allies? It's starting to look that way.