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By Yantoultra Ngui, Kane Wu and Fanny Potkin

SINGAPORE/HONG KONG, May 7 (Reuters) - U.S.-listed ride-hailing and food delivery firm Grab GRAB.O is looking to strike a deal to take over smaller Indonesian rival GoTo GOTO.JK in the second quarter, two sources with knowledge of the matter said.

Singapore-headquartered Grab has hired advisors to work on the proposed deal, the two sources added. The deal is subject to terms such as financing, which Grab is in discussion with banks, one of the sources added.

Both Grab and GoTo declined to comment.

Grab is looking to buy GoTo's businesses at around $7 billion, according to a separate source with knowledge of the matter. Jakarta-listed GoTo's shares have climbed 20% year-to-date, giving it a market value of around $5.8 billion, LSEG data showed.

Grab's shares on Nasdaq were up 2.4% so far this year, giving it a market value of nearly $20 billion, according to LSEG data.

GoTo will be selling off its international unit in Singapore to Grab, two separate sources familiar with the matter said. In Indonesia, GoTo will sell its entire operations except its finance arm to Grab, one of the two sources added.

Grab, backed by Uber UBER.N, offers services consisting of deliveries, mobility and financial services, among others, according to its website.

GoTo, whose investors include SoftBank and Taobao China Holding, described itself as Indonesia's largest digital ecosystem that provides e-commerce services and banking services, its website showed.

A merger between Grab and GoTo would create a giant in the ride-hailing industry in Southeast Asia dominating around 85% of the $8 billion market, according to data analytics company, Euromonitor International .

"The combined entity would hold a market share of over 91% in Indonesia, and almost 90% in Singapore," said David Zhang, Euromonitor International's insights manager of payments and lending in Asia.

"Markets especially in Indonesia and Singapore will impose strict scrutiny," he said, adding that the merger will likely be blocked by regulators in key markets in Southeast Asia.

Indonesian stockbroker BRI Danareksa Sekuritas' analyst Niko Margaronis, who covers GoTo, said that the Indonesian authorities may adopt a more pragmatic approach when assessing a potential merger, weighing the benefits of strengthening existing players and fostering long-term economic value.

Antitrust scrutiny has intensified significantly against the backdrop of rising cost of living driven by uncertain global macroeconomic environment made worse by U.S. President Donald Trump 's tariffs .

In March, Uber terminated its $950 million bid for Delivery Hero's DHER.DE Foodpanda business in Taiwan after Taiwan blocked the proposed deal on anti-competitive concerns and worries over it could incentivize Uber to raise prices.

(Reporting by Yantoultra Ngui, Fanny Potkin in Singapore and Kane Wu in Hong Kong, Editing by Louise Heavens)

((Yantoultra.Ngui@thomsonreuters.com;))