Veronica Wu, former Tesla China president

Tesla Motors Inc, the United States-based producer of electric cars, said that its top manager in China is leaving the company.

Tesla China President Veronica Wu has resigned, said Richard Lan, a Beijing-based company official, who declined to disclose when her last day would be.

Tom Zhu, who now heads the carmaker's charging network development in China, will assume operational leadership in the country, Tesla said in an e-mailed statement. Wu did not immediately respond to calls and text messages to her mobile phone.

"We remain confident in the Chinese market," the company said in an e-mailed statement. "We'll continue to focus on providing an amazing experience to all customers, so that they can become our advocates and help us accelerate the transition to sustainable transportation."

Wu's resignation comes less than nine months after Tesla chose her as its China head, replacing Kingston Chang, who left in March. She joined the company last December from Apple Inc. The carmaker started delivering its Model S sedans in the world's biggest auto market in April and expects to start building them in China within three to four years.

"Tesla counts on China as one of their main drivers of growth after California, and it might have been more difficult than they thought," said Jochen Siebert, a Shanghai-based managing director at JSC Automotive Consulting. "They need to succeed in China, as it is one of the markets that is open to electric vehicles."

Zhu joined Tesla in April and was a co-founder at Kaibo International, which provides project and construction management services, according to Tesla. He has an MBA from Duke University's Fuqua School of Business in the US, the company said.

Tesla has nine stores and service centers in six Chinese cities and has tied up with companies including China Unicom and Soho China Ltd to build charging stations in the country.