Uber has revealed it is under investigation by a string of tax authorities in the US and abroad.
The ride-hailing firm said in a filing today that the Internal Revenue Service (IRS) has launched a probe into its taxes for 2013 and 2014.
Uber said it was also under scrutiny from “various state and foreign tax authorities”.
The tech giant, which floated on the New York Stock Exchange last month, said it was “highly uncertain” when the audits would be resolved.
But it said it expected a reduction in unrecognised tax benefits of at least $141m (£111m) within the next twelve months.
Uber said it had put “adequate” reserves aside to cover any additional tax bills, but warned it could face tax adjustments in major jurisdictions including the UK, Australia, Brazil and Singapore.
HMRC last month opened an investigation into Uber over allegations it owes roughly £1bn in unpaid VAT relating to the self-employed status of its drivers.
Uber has suffered a challenging period of trading since its $82bn initial public offering, and last week posted an eye-watering loss of $1bn for the first quarter.
The firm has pumped more money into its Uber Eats food delivery service, as it looks to shake off competition from rivals such as Lyft and Deliveroo.