The US embassy in Berlin has said the use of untrusted vendors by allies in their 5G mobile networks could jeopardise future sharing of intelligence.
An embassy spokesman declined to comment on a letter that the Wall Street Journal said the Trump administration had sent to Berlin warning that it would scale back data-sharing with German security agencies if China's Huawei got a role in Germany's next-generation mobile infrastructure.
However, he said, use of untrusted vendors in allies' networks could raise questions about the integrity and confidentiality of sensitive communications with a country.
"This could in the future jeopardise nimble cooperation and some sharing of information," the spokesman added.
What is the issue with Huawei?
Shenzhen-based Huawei is the world’s biggest producer of telecommunications network equipment and it also competes with Apple and Samsung as a smartphone maker.
The company and its founder Ren Zhengfei have long been suspected of having close ties with China’s military and intelligence agencies.
Huawei denies that it works with the Chinese government and that its products are designed to facilitate spying.
Asked about Washington's warning that it would scale back data-sharing with Berlin if China's Huawei was allowed to participate, German Chancellor Angela Merkel said on Tuesday that the country will define its own security standards for a new 5G mobile network.
"Security, particularly when it comes to the expansion of the 5G network, but also elsewhere in the digital area, is a very important concern for the German government, so we are defining our standards for ourselves," Merkel said. "We will also discuss these questions with our partners in Europe, as well as the appropriate offices in the United States."
Peter Beyer, a member of Chancellor Angela Merkel's conservatives and the country's transatlantic policy coordinator, added while Germany shares US concerns about giving Huawei a role in a next-generation mobile network, an independent decision on how to safeguard its security needs to be made.
'US warning goes too far'
Beyer underscored the importance of setting the highest security standards for the new 5G infrastructure which is essential for new technology developments such as self-driving cars.
"There are justified doubts about whether a company that is close to the Chinese government can credibly achieve these security standards, which are imperative for such highly sensitive applications," he said in a statement.
"It is self-evident that we will reach all decisions independently and responsibly in line with our interests, also vis a vis our partners."
Meanwhile, Huawei criticised Washington's intervention with Vincent Pang, the company's chief for West Europe, saying the US warning went too far.
"In my opinion, a country should not use its political power to harm a commercial business," Pang was quoted as saying by business daily Handelsblatt.