Uber rival Grab has secured a new $2.5bn (£1.9bn) fundraising round, describing it as the biggest ever round of investment in South East Asia.
Japan's Softbank and DiDi Chuxing, which dominates the car-sharing market in China, will invest up to $2bn, with new and current investors to provide the remaining $500m.
"We're encouraged that these two visionary companies share our optimism for the future of South East Asia and its on-demand transportation and payments markets, and recognize that Grab is ideally positioned to capitalize on the massive market opportunities," said Grab chief executive Anthony Tan.
"With their support, Grab will achieve an unassailable market lead in ridesharing, and build on this to make GrabPay the payment solution of choice for Southeast Asia."
Funded in 2012 in Malaysia, Grab covers seven countries in South East Asia and is by far the most popular car-sharing firm in the region with a market share of 95% in third-party taxi-hailing and 71% in private vehicle hailing.
Grab operates the largest transportation network in South East Asia and is one of the most frequently used mobile platforms in the region with nearly 3 million daily rides
The company has steadily fought off competition from Uber in the region and the partnership with DiDi Chuxing is particularly significant, given the Chinese company virtually ended Uber's ambitions in the world's second-largest economy last year.
DiDi, which controls an 87% market share of the taxi-hailing market in China, merged with Uber China last year. DiDi's CEO and founder Cheng Wei, praised Grab for establishing a leadership in South East Asia's internet economy.
"By deepening our strategic partnership, DiDi and Grab reaffirm our shared commitment to innovating localised solutions to global urban development challenges from the world's fastest growing marketplaces," he added.
"Both companies look forward to working together with communities and policymakers across Asia to fully embrace the extraordinary opportunities in the upcoming transportation revolution."