UK Prime Minister Boris Johnson is set to decide on Huawei's role in the country's 5G networks.

Britain's National Security Council (NSC), chaired by Johnson, will meet on Tuesday to discuss its plans around banning the Chinese telecom giant.

Media Secretary Oliver Dowden will announce a decision to the House of Commons later in the day.

This comes amid sustained pressure from the Trump administration, pushing Johnson to reverse his January decision to grant Huawei a limited role in UK's 5G networks.

The immediate excuse for the U-turn in the policy is the impact of new U.S. sanctions on chip technology, which London says affects Huawei's ability to remain a reliable supplier in the future.

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It is unclear how far Johnson will go on Tuesday. Operators already had to cap Huawei's role in 5G at 35 percent by 2023. Reducing it to zero over an additional two to fours years is now being discussed, although some telecoms firms have warned that going too fast could delay key technology and disrupt services.

Huawei's UK Chairman John Browne told CGTN's Global Business last Wednesday that Britain is risking throwing away its long-standing relationship with China if it bans Huawei from its 5G networks as requested by the United States.

China's ambassador to the UK, Liu Xiaoming, warned this week that getting rid of Huawei would send a "very bad message" to Chinese business and would damage trust.

"You cannot have a golden era if you treat China as an enemy," said Liu.

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Asked about Huawei in June, Johnson said he would protect critical infrastructure from "hostile state vendors." Justice Secretary Robert Buckland said on Monday the "priority" in the decision would be national security.

The United States claims Huawei, the world's biggest producer of telecoms equipment, is an agent of the Chinese government and cannot be trusted.

Huawei denies it spies for China and has said the United States wants to frustrate its growth because no U.S. company could offer the same range of technology at a competitive price.

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In January, Johnson defied Trump by allowing so-called high-risk companies' involvement in 5G – including Huawei – to be capped at 35 percent. He excluded such companies from the sensitive 5G "core," where data is processed, as well as critical networks and locations such as nuclear and military sites.

Britain's major telecoms networks have said they need at least five years, and ideally seven, to remove Huawei.

BT CEO Philip Jansen urged the government on Monday not to move too fast on a ban, cautioning there could be outages and even security issues if it did.

"If we get to a situation where things need to go very, very fast, then you are into a situation where potentially service for 24 million BT Group mobile customers is put into question - outages," he told BBC radio.

Huawei has said the implications of the U.S. sanctions are not yet clear, and it has urged Britain to wait.

(With input from Reuters)