Huawei faces fresh challenges in Europe after France’s Orange said it would not hire the Chinese firm to build its next-generation network and Germany’s Deutsche Telekom announced it would review its vendor strategy.

The shift by the national market leaders, both partly state owned, follows Huawei’s exclusion on national security grounds by some US allies, led by Australia, from building their fifth-generation (5G) mobile networks.

US officials have briefed allies that Huawei is ultimately at the beck and call of the Chinese state, while warning that its network equipment may contain “back doors” that could open them up to cyber espionage.

Huawei says those concerns are unfounded. Tensions have been heightened by the arrest of Huawei’s chief financial officer in Canada for possible extradition to the United States.

“We don’t foresee calling on Huawei for 5G,” Orange CEO Stephane Richard told reporters in Paris. “We are working with our traditional partners – they are Ericsson and Nokia.”

Richard said he considered the security concerns to be legitimate: “I absolutely understand that all of our countries, and the French authorities, are preoccupied. We are too.”