A humanoid robot bubble could be brewing, warned China’s leading economic planning agency on Thursday. The alert comes amid growing fears that a bubble in a related industry — AI — is about to burst.

Speaking at a press briefing, National Development and Reform Commission spokesperson Li Chao said China’s humanoid robotics industry needs to balance “the speed of growth against the risk of bubbles.” Investment has been pouring into the sector despite there being few proven use cases for the bots, Li said, risking a flood of “highly similar” models as funding for research and development shrinks.

More than 150 humanoid robotics companies are operating in China, Li said. More than half are startups or entrants from other industries.

The warning marks a rare note of caution from Beijing for an industry it has declared vital for future economic growth. Earlier this year, China designated embodied intelligence — the technology behind humanoid robotics — a national priority.