Uber Technologies Inc. and Google were seen as allies after the search giant invested $258 million in the ride-hailing firm in 2013. But the companies are starting to act more like competitors.

A top Google executive who held a seat on Uber’s board announced his resignation this week after Uber allegedly shut him out of meetings to limit his knowledge of the company’s plans for self-driving vehicles. Google, meanwhile, is expanding its reach into ride-hailing by reportedly turning its navigation app Waze into a potential competitor to Uber.

Unlike Uber, which takes a cut of the fare and compensates drivers, the Waze program requires riders pay their drivers for only the cost of gas — typically 54 cents per mile, the IRS’ mileage reimbursement rate.

Neither Uber nor Google responded to requests for comment.