EU countries have no reason to use 5G mobile technology from Huawei because Sweden's Ericsson, Finland’s Nokia and South Korea’s Samsung are on par with the Chinese group in the field, a senior US diplomat has said.

Robert Strayer, deputy assistant secretary for cyber, international communications and information policy at the US State Department, said on a visit to Lisbon it was "necessary to demystify" the notion that Huawei is more advanced in 5G.    

Washington wants its allies to ban Huawei, the world’s largest producer of telecoms equipment, arguing the use of its kit creates the potential for espionage by China - a claim denied by Huawei and Beijing.

Its stance has sparked tensions with allies such as Britain, whose Prime Minister Boris Johnson has granted Huawei a limited role in building a 5G mobile network.

Mr Strayer said the United States is encouraging European countries to think carefully about the security and economic implications of rushing forward with using Huawei’s technology.

"There is no way to fully mitigate any type of risk except the use of trusted vendors from democratic countries," he told reporters.

"The good news is Ericsson, Nokia and Samsung all provide 5G technology that is on par with the one Huawei is providing today. They are leading the world in the type of technology they have."

Huawei says it spent $15 billion last year on research to help it achieve market leadership 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.

Mr Strayer said Western vendors such as Ericsson and Nokia will use an open architecture with more functionality, creating opportunities for companies in the United States and Europe to provide compatible equipment.

American companies like Dell, Cisco, Juniper and VMware "want to play a future role", he said, seeing many European companies also getting involved.    The European Union has said it would allow members to decide what part China's Huawei can play in 5G networks.

Portugal last month approved guidelines for its 5G strategy and launched a working group to permanently monitor the risks and security of this network.

Huawei loses legal challenge against US ban

Meanwhile, Washington has the right to block US federal agencies from buying products by Huawei on cybersecurity grounds, a judge has ruled, dismissing the Chinese telecom giant's legal challenge to a purchase ban.

Huawei filed the suit nearly a year ago, claiming that Congress had failed to provide evidence to support a law that stopped government agencies from buying its equipment, services, or working with third parties that are Huawei customers.

The dispute was one of several fronts in a bruising trade war between Beijing and Washington, which has accused the tech firm of spying and stealing trade secrets from American companies.

Huawei has denied the claims and accused the US of trying to put the company out of business through an "unconstitutional" restriction on its access to the American market.

But yesterday's court ruling in the United States found there was no constitutionally guaranteed right to a contract with the federal government.

The ban was also justified in the context of a congressional investigation "into a potential threat against the nation's cybersecurity," wrote US District Judge Amos Mazzant.

Huawei said in a statement that it was disappointed with the ruling and would "continue to consider further legal options."

Washington has long considered Huawei a possible security danger due to the background of founder Ren Zhengfei, a former Chinese army engineer.

It has warned that the company's systems could be manipulated by Beijing to conduct espionage and disrupt critical communications in foreign countries, and is urging countries to shun the firm. 

Concerns have intensified with Huawei's rise to become a world leader in telecom networking equipment and one of the top smartphone manufacturers alongside Samsung and Apple.

But the firm is expected to play a major part in the rollout of ultra-fast 5G networks that will allow wide adoption of next-generation technologies such as artificial intelligence.

Pentagon chief Mark Esper warned Saturday that Huawei's involvement in Europe could jeopardise the NATO military alliance. 

The warning came days after the US ambassador to Germany said President Donald Trump had threatened to end intelligence-sharing deals with countries that dealt with the firm. 

Last week the US also slapped the company with criminal charges for an alleged "decades-long" effort to steal trade secrets from American companies.

Huawei's chief financial officer Meng Wanzhou was arrested in Canada in 2018 on a US warrant in a related probe into her company's alleged violation of US sanctions. 

She is under house arrest awaiting a ruling on whether she will be extradited to face charges south of the border.