Uber Technologies‘ chief technology officer has resigned after less than a year on the job, a media report said.

Sukumar Rathnam, the outgoing CTO, will remain at Uber for several more weeks to help with the transition, according to an email he sent to his team Tuesday that was seen by Bloomberg. The company has no immediate plans to replace him, a spokesman for Uber told the news outlet.

“Sukumar is an incredible talent, and I’m grateful for his leadership and everything he has done for Uber over the last year,” Uber CEO Dara Khosrowshahi wrote in an email to staff.

Neither executive provided a reason for the departure in their emails. Rathnam didn’t immediately respond to a request for comment. Business Insider first reported on Rathnam’s departure, Bloomberg noted.

Uber’s eight engineering leads will now report directly to Khosrowshahi, Bloomberg said.

Rathnam’s predecessor, Thuan Pham, spent seven years at Uber before stepping down last year. In an interview with Bloomberg shortly after, Pham said he disagreed with Khosrowshahi’s approach to self-driving cars. By the end of the year, Uber changed course and sold the autonomous vehicle division.

Bloomberg noted Uber touted Rathnam as a high-profile hire when he joined nearly a year ago. He was previously a vice president at Amazon.