Chinese authorities have ordered the country’s top internet and technology companies to list restrictions that bar competitors from posting their links, a practice still prevalent despite several warnings from officials.

During a high-level meeting attended by some of the country’s leading companies, the Ministry of Industry and Information Technology emphasized its stand in creating a healthy internet environment, ordering companies to stop blocking cross-linking from competitors.

Many of the country’s largest internet companies often block users from posting links from rivals on their platforms — for example, links from Alibaba’s ecommerce platform Taobao cannot be posted on Tencent’s messaging app WeChat.

“Ensuring the legitimate sharing of URL links is a basic requirement for the development of the internet,” Zhao Zhiguo, spokesperson for the ministry, said during the meeting.

In July, the ministry ordered an inspection of major internet companies but found some companies either hadn’t grasped the issue or they were unsure of what they were supposed to do. Representatives of major tech giants, including Alibaba, Tencent, and ByteDance, who attended the meeting vowed to open their “walled gardens” and make links accessible on each other’s platforms.

Both Alibaba and Tencent said they “strongly support” the ministry’s directive and “will comply” with them.

In April, Alibaba was slapped with a ($2.8 billion) fine after its food delivery platform ele.me was found in violation of China’s antitrust laws. China enacted its antitrust guideline in February to stop monopolistic behavior in the country’s internet sector.

“Restricting normal access to internet links without proper reason affects user experience, damages the rights of users, and disrupts market order,” Zhao said.