Uber confirmed Wednesday that the company's head of finance is leaving, just after the on-demand ride service trimmed its quarterly loss to $708 million on rising revenue.

Gautam Gupta will depart Uber in July to become chief operating officer at a younger startup in San Francisco, according to the company.

"Over the last four years, (Gupta) has been indispensable in helping build Uber from an idea into the business it is today," founder and chief executive Travis Kalanick said in a statement.

"We couldn't have done it without him, and I will miss his energy, focus and infectious enthusiasm."

Uber said that its revenue during the first three months of this year rose some 18 percent to $3.4 billion, but the company logged a loss of $708 million without taking into account stock compensation for employees.

Uber cited the numbers as progress, given that losses in the preceding quarter totaled $991 million.

"These results demonstrate that our business remains healthy and resilient as we focus on improving our culture, management and relationship with drivers," an Uber spokesperson said.

"The narrowing of our losses in the first quarter puts us on a good trajectory towards profitability."

Uber has seen a shake-out in its executive ranks as it works through a series of scandals that included disclosures about a culture of sexism, cut-throat workplace tactics, covert use of law enforcement-evading software, and release of a dash-cam video showing Kalanick berating and cursing at one of Uber's drivers.

Uber said Tuesday that it had fired an engineer accused in a trade secrets suit involving files he purportedly purloined from Alphabet's self-driving car unit Waymo.

The case stems from a lawsuit filed in February by Waymo, formerly known as the Google self-driving car unit, which claimed a former manager took a trove of technical data with him when he left to launch a competing venture that went on to become Otto and was later acquired by Uber.