The United States on Monday warned Germany about future "information sharing" if it uses "untrusted vendors" in its 5G telecom infrastructure amid debate over whether Chinese IT giant Huawei is an espionage risk.
The Wall Street Journal reported that US Ambassador Richard Grenell sent a letter to German Economy Minister Peter Altmaier on Friday warning that in such a case the US could scale down intelligence and other information exchanges.
A US embassy spokesperson told AFP on Monday it would not comment on diplomatic communications, but added that its position on 5G network security was well known.
"To the extent there are untrusted vendors in the networks of an ally, that could raise future questions about the integrity and confidentiality of sensitive communications within that country, as well as between that country and its allies," the spokesperson said.
"This could in the future jeopardise nimble cooperation and some sharing of information. We are engaging intensively with our allies on how to secure our telecommunications networks to ensure continued interoperability."
German minister Altmaier confirmed he had received the letter, but told AFP he could not comment on its contents, adding: "We will respond quickly". Germany, like other EU countries, has relied heavily on US intelligence on terror and other threats provided by the National Security Agency, the Central