China is making it harder to get around its Great Firewall.

China's Ministry of Industry and Information Technology has announced a 14-month "clean up" of internet access services, which includes a crackdown on virtual private networks, or VPNs.

The new regulations require VPN services to obtain government approval before operating. Using a VPN without permission is also prohibited.

VPNs use encryption to disguise internet traffic, allowing users in China to bypass the Great Firewall to access censored and restricted websites. The services typically cost around $10 a month.

#China's crackdown on VPNs at odds with Pres. Xi's call for global connectivity -- my report for @cnni @cnntoday https://t.co/KmI91R1tZJ — Sherisse Pham (@Sherisse) January 25, 2017

China's vast censorship apparatus -- known as the Great Firewall -- prevents the country's 730 million internet users from accessing information on sensitive subjects like Tibet or the deadly 1989 crackdown on Tiananmen Square protests.

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Foreign news outlets, search engines like Google (GOOG) and social media sites including Twitter (TWTR) and Facebook (FB) are blocked. Harsh criticism of China's government is also censored.

The effort has left Chinese Internet users with a World Wide Web that bears little resemblance to the uncensored internet.

Since China began controlling internet access in the mid-1990s, activists and developers have worked to develop tools that help people circumvent the firewall.

Related: Apple yanks New York Times apps in China

Government agencies respond regularly with new regulations that tighten China's grip on the internet.

Earlier this month, Apple pulled New York Times apps from the App Store in China, a move that may have been connected to new rules stipulating mobile phone apps must not disseminate banned content.

Last November, Beijing approved a controversial cybersecurity law requiring service providers to collect personal information and prevent data collected in China from leaving the country.

In 2015, Chinese state media described a blackout of VPN service providers as a "healthy development" for the internet.

-- Christy Chen contributed to this report.