MANILA - The country's antitrust watchdog said Monday it was considering an investigation into ride-sharing service Grab's acquisition of rival Uber for violation of competition laws.

Grab will have a "virtual monopoly" of the ride-sharing market in the Philippines with Uber's exit until new players come in, the Philippine Competition Commission said in a statement.

The PCC said it met with representatives of Uber and Grab to determine whether the size of the companies and the transaction would meet the thresholds for the antitrust body to step in.

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"A merger or acquisition review using competition lens will determine whether the merger of two players in the ride-sharing market will substantially lessen competition," the PCC said.

"PCC recognizes that the exit of Uber in the Philippines will put its rival Grab in virtual monopoly in the ride-sharing market until the new players come into operation," it said.

Uber and Grab announced the deal last Monday, marking the US company's second retreat from an Asian market. It earlier sold off it's operations in China to homegrown Didi Chuxing.

Uber will have a 27.5-percent stake in Grab, which competes in Southeast Asia Indonesia's Go-Jek.

The PCC said the participation of Uber and Grab in consultations on Monday showed their "willingness to comply" with the Philippine Competition Act.

The PCC said the deal would meet the thresholds that would require an investigation if the size of either Uber or Grab breaches P5 billion, and "assuming the transaction involves the acquisition of Uber assets inside and outside" the country.

The thresholds would also be met if the aggregate value of Uber's assets in the Philippines exceeds P2 billion and if aggregate gross revenues generated into the country by assets acquired inside and outside the Philippines collectively exceed P2 billion.

Antitrust monitors in Singapore and Malaysia are investigating the deal.

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