Google has warned of security risks if Huawei smartphone users try to sideload apps such as Gmail and YouTube just as the Chinese tech giant is set to unveil new models.

Huawei Technologies, the world’s largest telecoms equipment company, is prohibited from using Google services include Gmail, Maps, YouTube and the Play Store under a US government ban that went into effect in May last year.

Huawei had planned to unveil new smartphones, PCs, tablets and Internet of Things products at MWC Barcelona, but show organizers cancelled the event, the world’s biggest for the mobile industry, after several major exhibitors pulled out over coronavirus fears.

An attendee uses his smartphone near an advertisement for the Mate 30 phone from Chinese technology firm Huawei at the PT Expo in Beijing on October 31, 2019. (Picture: AP)

Instead, Huawei has scheduled a webcast on Monday to announce a new Honor-brand V-30 series smartphone, an updated Huawei Mate X model, as well as wearable devices.

The ban on Huawei using Google core apps was seen as damaging to the Chinese company as it undercut its ability to compete in smartphone markets outside China, where Google apps have become an indispensable part of many users' lives.

When Huawei’s Mate 30 became its first flagship phone to ship without Google apps built-in, users quickly found ways to work around the ban by downloading the apps themselves.

However, on Friday Google issued a warning about such workarounds.

“Sideloaded Google apps will not work reliably,” Tristan Ostrowski, Google’s Android & Play legal director, said in a post on Friday. “Sideloading Google’s apps also carries a high risk of installing an app that has been altered or tampered with in ways that can compromise user security.”

Sideloading refers to installing apps device-to-device without using the official Google Play store.

The clarification was made because Google has “continued to receive a number of questions about … new [Huawei] models launching now or earlier models launched” after the US trade ban, Ostrowski said.

Google still provides security and app updates on Huawei devices available before May 16, 2019.

Despite the challenges posed by the US trade ban, Huawei has resolved to stay in the international smartphone market. Late last month, it rolled out an improved version of its self-developed ecosystem, Huawei Mobile Services, to users worldwide.

A man browses his smartphone outside a Huawei store at a shopping mall in Beijing on December 11, 2018. (Andy Wong/AP)

The company said its app store, AppGallery, had more than 390 million active users worldwide as of November, still low compared with Google Play which had more than 2 billion monthly active users in the fourth quarter.

“AppGallery is a top platform for Huawei users to access secure and high-quality apps. We encourage our users to explore apps through AppGallery or other secure channels,” Huawei said in a statement in response to Google’s latest risk warning.

“Protecting the privacy and security of our users is Huawei’s top priority. Huawei is working with global app developers, through different initiatives, to continuously improve user experience,” the company added.

Nicole Peng, vice-president of mobility at Canalys, said the Google statement was not just a warning about security risks. Issued by the legal team, “it was a very clear statement on what kind of Huawei devices are legally and officially supported by Google, which has been vague since May 16 2019,” she said.

The US sanctions have hit the Shenzhen-based company’s smartphone business outside mainland China, with western consumers reluctant to purchase the devices without Google services.

To compensate, Huawei has stepped up efforts in its domestic market, with its brand accounting for 42 per cent of the Chinese market in the third quarter of 2019, cutting the market shares of domestic rivals such as Vivo, Oppo and Xiaomi, figures from IDC showed.

Huawei’s annual Developer Conference has been a key part of its strategy to develop a new ecosystem of apps to make up for the loss of Google. At the 2019 developer conference Huawei officially unveiled its self-developed operating system Harmony, saying that migrating apps over from Android would be relatively easy but that it would prefer to continue using Google’s Android OS on its smartphones.

“Time is not on Huawei's side as the existing models have shelf lives expiring in six to nine months,” said Peng. “It is forcing Huawei to push even more aggressively with new devices [loaded] with HMS instead.”

Huawei’s efforts to develop its own ecosystem saw a setback this year after the company postponed its 2020 developer conference and then replaced it with a webcast amid the ongoing coronavirus health crisis, which has killed over 2,500 people globally.