Grab is considering raising more funds from strategic investors, the president of Southeast Asia's top ride-hailing firm said, after raking in over $4.5 billion in the region's largest private financing round that included SoftBank's Vision Fund.

The Singapore-based firm continues to see strong interest from global investors after securing nearly $1.5 billion from the Vision Fund in a year-long round, Ming Maa told Reuters.

The financing round kicked off shortly after ride-hailing giant Uber surrendered its Southeast Asian operations to Grab in March 2018 after a costly battle and in return took a 27.5 percent stake in Grab's business.

"We continue to see just a tremendous amount of investor interest around the world, and we may consider upsizing this financing in the future," said Maa, a former SoftBank executive, who was instrumental in SoftBank's earlier investments in Grab before joining the startup in 2016.

Maa, 42, said Grab was keen to tie up with more partners that could provide the company with a complementary set of technologies or services to help it expand its offerings.

Citing a valuation of $11 billion, research firm CB Insights had ranked Grab among the top 15 unicorns globally before the announcement of the latest funding from SoftBank.

Maa said Grab is not focused on an IPO even as U.S. ride-hailing companies Uber and Lyft kicked off the process to list this year. "It is accurate to say we are absolutely not focused on an IPO or an IPO timeline right now," Maa said.

"For now, we are all heads down focused on growing the market, growing the business as opposed to a capital markets transaction," he said.