BEIJING — When President Xi Jinping announced measures to further open up China’s auto industry to foreign carmakers, the global industry initially cheered.

Now the cheering has stopped.

As details are emerging, foreign auto executives attending China’s annual auto show in Beijing this week said Mr. Xi’s initiative was too narrow and vague to change business on the ground. That means the initiative may not be a strong enough starting point for talks to stave off the Trump administration’s threats to impose tariffs on $150 billion in Chinese-made goods.

Central to Mr. Xi’s plan is that it will allow foreign automakers to own Chinese factories, instead of working through a 50-50 Chinese partner, as is currently required. But auto executives in Beijing said they were comfortable with the current system.

“It would be crazy to think you can do it all yourself, in a market that is so different,” said Trevor Worthington, Ford’s vice president for product development in Asia and the Pacific.