The company will have to drop exclusivity deals with partners and intermediaries. It'll also cap its fare increases (beyond inflation) to 10 percent for its most common Uber X and Careem Go tiers. Surge pricing, meanwhile, can't jump beyond 2.5 times the normal rate and can't be applied to more than 30 percent of trips each year.

The Careem buyout could be crucial for Uber. The firm has spent the past few years retreating on the international stage, having sold its Southeast Asian business to Grab, partnered with Didi in China and merged its Russian unit with Yandex. This is an expansion that could give it more clout beyond (relatively) safe regions like North America and Europe.