Chinese telecoms giant Huawei said Thursday it is mounting a legal challenge to the ruling by the U.S. Federal Communications Commission (FCC) banning the government’s Universal Services Fund from being used to buy equipment from the company.

Last month, the FCC voted unanimously to forbid American wireless carriers from using the government fund to buy equipment from Huawei and its rival ZTE on the grounds that the two Chinese companies pose national security threats.

Huawei has filed a petition to the U.S. Court of Appeals for the Fifth Circuit demanding a suspension of the FCC order, claiming it is “unlawful on the grounds that it fails to offer Huawei required due process protections,” the company announced during a news briefing in the southern Chinese city of Shenzhen.

Although U.S. carriers have generally steered clear of Huawei equipment for some time, some in more rural and remote areas depend on the Chinese company’s gear for their mobile networks.

Alan Fan, Huawei’s Vice President of IP Strategy and International Legal Policy, again hit back at U.S. claims that the Chinese government could leverage Huawei’s overseas telecoms equipment for espionage purposes, saying no Chinese law required Huawei to deploy such “backdoors.”

Prohibiting Huawei sales would delay the rollout of the U.S.’ superfast 5G wireless network by six to 18 months and cost the country billions in lost GDP, Fan added, citing third-party reports.

“Banning a company like Huawei, just because we started in China — this does not solve cybersecurity challenges,” Huawei’s Chief Legal Officer Song Liuping said at the press conference.

Read the full story later today on Caixin Global.

Contact reporter Mo Yelin (yelinmo@caixin.com)

Related: U.S. Telecom Regulator Bans Carriers From Using Public Fund