(Beijing) — China’s new crackdown on unlicensed virtual network providers (VPNs) is aimed at parties engaged in unauthorized cross-border online activity and shouldn’t affect international companies using legal channels, the nation’s telecom regulator said.

The Ministry of Industry and Information Technology (MIIT) announced the crackdown on its website on Sunday, outlawing dozens of popular VPN services that help web surfers get around China’s blockage of sites that address sensitive topics. Such services enable access to blocked sites by routing requests that originate from the Chinese mainland through servers located elsewhere.

The MIIT’s “rectification campaign” will run until March 2018, according to the original notice.

The move raised concerns that some multinational organizations might lose access to their VPNs, which are needed in China to view pages on services like Google’s search engines and news sites like Reuters, Bloomberg and the New York Times, and on social networking sites like Facebook and Twitter.

Addressing those concerns, the MIIT issued a follow-up statement on Tuesday in a question-and-answer format discussing the reasons for the crackdown and what it hoped to achieve through the campaign.

The statement said the crackdown is aimed at service providers that have not been approved by the ministry, including companies and individuals who were unauthorized to offer international telecom services. China tightly regulates such services, which are mostly confined to the nation’s three big state-run carriers — China Mobile, China Telecom and China Unicom.

It said foreign trade companies and multinationals that require such private services can turn to officially authorized offerings, adding the new action “won’t have any impact on their general business.”

Several popular local and international VPN operators, including Wow Shadow and Astrill, said their services were stable immediately after the announcement of the crackdown.

The regulation comes six weeks before the annual meeting of China’s national legislature in Beijing. Many companies and individuals complained that their paid-for VPN services were not functioning for over a week in March 2016, when the National People’s Congress met.

China began filtering information on the Internet in the late 1990s, citing national security.

Contact writer: Yang Ge (geyang@caixin.com)