China’s Ministry of Industry and Information Technology held a meeting last week with at least a dozen automakers to issue tightened rules over driver assistance technology, in a move that may slow the deployment of such systems by manufacturers.

According to a statement released by the agency Wednesday, automakers will now be required to be clearer about what the technology can and can’t do and improve safety precautions. Manufacturers also can’t exaggerate or falsely advertise driver assistance features.

But one person familiar with the conversations that took place during the meeting said the discussions went further. Officials also laid out rules to avoid describing advanced driver assistance systems as “self-driving” and to encourage drivers to keep their hands on the steering wheel while using such features, the person said, asking not to be identified because they’re not authorized to speak publicly.

MIIT officials also told carmakers they should not hold test events involving customers before a product is finalized and they shouldn’t allow drivers to use the self-parking feature unless they are actually in the vehicle, they said. In China, several carmakers have functions that allow a driver to step outside their car while the car parks itself kerbside.

Representatives from MIIT didn’t respond to a request for comment.

The new rules could mean the roll out of upcoming smart cockpit and driver assistance systems are delayed for months. Li Auto Inc. and Xpeng Inc. are among carmakers that have organized test drives in the past where they invite thousands of users to take part and help assess their technology. Those sort of events would be banned going forward.

More broadly, they’ll come as a blow to most automakers considering smart cars packed with intelligent driving features are such a selling point in China. Tesla Inc. launched a product it markets as Full Self Driving in China earlier this year while BYD Co. said it plans to make advanced driver assistance systems available in most of its models at no extra cost.

The additional restrictions also come just weeks after an accident involving a Xiaomi Corp. SU7 electric vehicle killed three people. The car had Navigate on Autopilot turned on less than 20 minutes before the crash.

Alerts were issued because the driver apparently wasn’t holding on to the steering wheel. Seconds after another warning was sent about obstacles in the road and the driver then retook control of the wheel, the car crashed into concrete fencing on the side of the road. Police are still investigating the accident.

Even before the fatal Xiaomi accident officials in China had begun to put guardrails around driver assistance technology.

In February, guidelines were issued about over-the-air (OTA) software updates, which carmakers routinely use to update in-car smart cockpit and driver assistance systems.

One of the goals was to reduce the frequency of the updates, which authorities have come to see as hasty fixes for defective products. The new rules require detailed reports about the updates to be filed first to government agencies. Updates deemed to include major changes need to be approved before being rolled out, the ministry said in February.

Tesla is beginning to get the message. The Chinese name for FSD, which initially was a literal translation of the English version, was changed to “Advanced Driver Assistance Function” in March.