BEIJING — The fog of cyberespionage concerns surrounding Huawei has for years kept the Chinese technology giant largely out of the United States. Now it has cost the company potentially lucrative business in another country: Australia.

Huawei said on Thursday that the Australian government had barred it and another Chinese company, ZTE, from providing equipment to support the country’s new telecommunications networks. Mobile carriers around the world have been preparing to build infrastructure using fifth-generation, or 5G, wireless technology, which promises to enable the ultrafast communications necessary for technologies such as self-driving cars.

On Twitter, Huawei called the decision an “extremely disappointing result for consumers.” In a statement, the company said it “will continue to engage with the Australian government, and in accordance with Australian law and relevant international conventions, we will take all possible measures to protect our legal rights and interests.”