Uber also said in a filing on Tuesday that various state and foreign tax authorities were looking into its taxes.

The company's shares, which closed up 2pc on Monday, were down 1pc in premarket trade.

Uber was the biggest of a group of Silicon Valley startups to go public this year against the backdrop of a global stock market sell-off sparked by renewed trade tensions between the United States and China.

In its first quarterly report as a public company last week, Uber reported a $1 billion loss as it spent heavily to build up its food delivery and freight businesses.