Tesla CEO Elon Musk said he is confident that the European Union will soon approve the car company’s fully autonomous driving system. But emails from some European regulators show clear skepticism about the technology and its claimed safety benefits.

In April this year, the Dutch Road Authority (RDW) approved Tesla’s fully autonomous driving (FSD) technology. The Dutch Roads Authority is currently seeking EU-level certification for the system, with a key committee hearing scheduled for Tuesday.

Whether fully autonomous driving can be approved in Europe is crucial for Tesla, where the company is trying to regain market share. The electric car maker is launching a monthly subscription service for its fully autonomous driving feature, which allows the system to drive autonomously in certain road conditions but requires the driver to maintain a high level of concentration throughout.

According to reports, emails show that regulators in the Netherlands, Sweden, Finland, Denmark and Norway have raised multiple concerns about this technology, and these countries have a key say in Musk’s push for FSD approval.

Regulators are concerned about the system’s tendency to speed, the safety of driving on icy roads, and whether drivers can bypass in-vehicle anti-cellphone controls.

Regulators also expressed dissatisfaction with Tesla’s approach—the company publicly called on car owners to put pressure on regulators to release fully autonomous driving systems.

The European Commission will hear Dutch officials on Tuesday explain their reasons for approving Tesla's FSD.

If the FSD is to be formally approved by the EU, Commission members representing 55% of EU member states and covering 65% of the EU population must vote in favor. No FSD-related votes have been scheduled this week, and the committee's next two meetings are expected to be held in July and October.