India, April 29 -- Tesla Inc.'s Elon Musk made an unannounced trip to China on Sunday, seeking approval for driver-assistance software that could help arrest the carmaker's revenue decline.

The Tesla chief executive officer met with Premier Li Qiang, who as the Chinese Communist Party secretary for Shanghai helped the company set up what is now its top plant globally.

Musk was expected to meet officials about rolling out the system Tesla markets as Full Self-Driving, or FSD, a person with knowledge of the matter said. While the suite of features requires constant supervision and doesn't make Teslas autonomous, the company generates incremental sales in the US by charging $8,000 to buy FSD outright, or $99 a month for a subscription.

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