- The Trump administration issued another warning to the UK over Huawei, via its ambassador to Germany.
- Richard Grenell tweeted that Trump wanted to remind allies that dealing with Huawei would jeapordize intelligence-sharing.
- Boris Johnson's decision to let Huawei develop Britain's 5G network angered the Trump administration.
- The UK prime minister has cancelled a planned visit to Washington in March amid tensions.
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Donald Trump has issued another warning to Boris Johnson's UK government over its decision to defy the US and allow Chinese telecomms firm Huawei to develop its 5g network.
Richard Grenell, Trump's ambassador to Germany, on Sunday said the president told him to remind ally nations that doing deals with Huawei would jeapordisz intelligence-sharing with Washington.
He tweeted: "Donald Trump just called me from AF1 [Air Force 1] and instructed me to make clear that any nation who chooses to use an untrustworthy 5G vendor will jeopardize our ability to share intelligence and information at the highest level."
It is the Trump administration's latest swipe at Johnson's government after the UK prime minister made the controversial decision to give Huawei a limited but significant role in developing Britain's 5G network.
Johnson went ahead with the deal despite US warnings that it could give the Chinese state access to western intelligence-sharing.
The Trump administration was angered by the decision, with the president himself reportedly expressing his disapproval before hanging up in an "apoplectic" phone call with Johnson last month.
Since the call, Johnson cancelled a visit to Washington which was penciled in for March, and has no plans to visit the US until the summer.
Trump's threats about Huawei reportedly "irritated" the UK government, with Johnson frustrated at the president's failure to suggest any alternatives.
Following the "apoplectic" call, US Vice President Mike Pence said the Trump administration had made its disappointment with the UK "very clear to them."
Australian MPs cancel trip to London over Huawei row
The US is not alone in opposing Britain's decision to deal with Huawei.
The Australian government also shares Washington's concerns. Its parliament's intelligence and security committee recently cancelled a trip to London amid diplomatic tensions with the UK.
Committee members planned to visit Britain in April to meet with their UK counterparts, but cancelled the trip, according to the Sydney Morning Herald.
Several members of parliament in Johnson's own Conservative party have expressed their concern about letting Huawei develop Britain's infrastructure.
Last month a number of them made pointed comments about Johnson's decision during a House of Commons debate.
David Davis, a former UK senior government minister, said the only way to protect UK safety from the potential threat posed by Huawei was to "ban it" altogether.
Conservative MP Julian Lewis said the Chinese company is "intimately linked with the Chinese communist state and its deeply hostile intelligence agency."