Chinese telecoms giant Huawei expected its 2021 revenues to be around 634 billion yuan ($99.8 billion), said its rotating chairman Guo Ping in a letter to employees on Friday, which represents a nearly 30-percent decline compared to the previous year.

Guo said Huawei's overall performance in 2021 is "under expectations."

"We must maintain our strategies and rationally respond to uncontrollable external force," read the letter published on its website.

The U.S. has banned domestic companies from dealing with Huawei citing "security concerns" since 2019.

The 634-billion-yuan predicted revenues in 2021 are 28.9 percent lower than its 2020 revenues, which were 891.4 billion yuan.

"We are still facing a series of challenges in 2022," said Guo, adding the company will not change its ideals and pursuits despite external environment changes.

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