MANILA - The Philippines' antitrust watchdog said Tuesday it was investigating ride-sharing service Grab's acquisition of its rival, Uber, over concerns this would disadvantage consumers.

The inquiry of the Philippine Competition Commission will proceed even if the deal did not reach threshold amounts that would require such action, according to its chairman, Arsenio Balisacan.

Grab will capture 80 percent of the ride-sharing market once the deal pushes through, Balisacan said.

• Ride-hailing firm Grab buys Uber's SE Asia operations

"The market is already concentrated, the merger would result in even more concentration. This could result in higher fares, less choices for commuters, and prevent other parties from entering that market," Balisacan said.

US-based Uber sold its business to Grab, exiting another overseas market. It earlier sold its Chinese operations to Didi Chuxing. Regulators in Singapore and Malaysia are investigating the deal on concerns similar to that of the PCC.

A public hearing on the planned acquisition was scheduled on Thursday. Uber had announced that it will cease Philippine operations on April 8.

• Uber-Grab deal faces possible antitrust probe in Philippines
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