Donald Trump's surprise U.S. election win has left a "high degree of uncertainty" as markets parse potential policy scenarios, said Leif Lybecker Eskesen, senior vice president for economics and investment strategy at Singapore state investment fund GIC.

"Right now, there is this gap between rhetoric and reality," Eskesen said on Wednesday at the Emerging Asia Economic Forum held by INSEAD and the Institute of International Finance in Singapore. GIC manages upwards of $100 billion.

During his campaign, Trump used aggressive rhetoric on trade, immigration, taxes, regulation, infrastructure and a host of other issues. Now, it's not clear which policies he will actually pursue.

"We have to see how some of the nominations to the cabinet come out, what the agenda will be lined for the first 100 days and how to think about implementing it, so there's a high degree of uncertainty around that," Eskesen said. "The key thing now is to work with scenarios, permutations of the different kinds of policy outcomes."

GIC, which manages Singapore's foreign reserves, tends to be tight-lipped about its investments and strategies.The fund, which the Sovereign Wealth Fund Institute ranked as the 13th largest public fund globally and the eighth largest sovereign wealth fund, holds assets across 40 countries. It typically allocates around 9-13 percent of its portfolio toward property assets and was an active buyer after real estate prices crashed in the wake of the global financial crisis in 2008 and after the Asian Financial Crisis in the late 1990s. For the financial year ended March 31, the fund's annualized rate of return over 20 years was 4.0 percent over global inflation.

Eskesen said there were questions over how stimulative the Trump administration's fiscal policy would be and the composition of the package.

"That has significant implications for the sustainability of the lift to growth that will come from that," he said.