Singapore Prime Minister Lee Hsien Loong was among the first world leaders to congratulate Trump, 70.

“Congratulations to President-elect Donald Trump! His candidacy took many by surprise,” Lee wrote in a Facebook post.

“At each stage he defied expectations, and his journey has ultimately taken him to the White House,” Lee said in the message which was posted while the Republican nominee was delivering his victory speech in New York.

Lee added: “US voters have elected a president whom they feel best represents them. Singapore fully respects their decision. We will continue to work together with the United States to cultivate our strong ties”.

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Political and economic observers said the election result introduced uncertainty to the US-Singapore bilateral relationship.

“The uncertainty about the direction of America’s foreign and trade policies will be problematic for Singapore, given that our economy relies heavily on global trade,” said Bernard Aw, a Singapore-based economist with IHS Markit.

“Any rise in trade protectionism and threats to global security will have a strong negative impact on Singapore’s open economy.

“Increasing volatility in global financial markets, including major swings in commodity prices may also affect Singapore indirectly,” Aw said.

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Other observers said Trump could dial back President Barack Obama’s Asian “pivot to Asia” strategy involving the redeployment of military assets and increased trade with the Asia Pacific region. The move is largely seen as an effort to counter China’s rising clout in the region.

“A Trump victory clearly does not bode well for a continuation of the Obama trade and investment initiatives which have been the centrepiece of America’s pivot to Asia,” said David Adelman, a former US ambassador to Singapore.

Trump’s lack of a well known track record in Asia “presents a challenge to our friends and allies in the region,” said Adelman, a partner with the law firm Reed Smith.

Singaporeans living in the United States told This Week in Asia there was a sombre mood at gatherings held to watch the election results.

“People are deflated and everyone is shell shocked. Some people are sobbing,” said Shafali Gupta, a Singaporean who was at one such “election night party”.

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“There is a real sense that Trump is going to cook this country and the rest of the world…after all the things he has said, you don’t feel welcome here anymore,” said Gupta, a New York-based management consultant.

“Singaporeans like us are not going to be first people he is going to go after. We are here legally and in higher end jobs. Still, he has proven to be unpredictable, and you don’t know what he will do.”

Others were more stoic about the result. Divya Sangam, another US-based Singapore national, said “we move on and remind ourselves it’s only four years”.

“Doomsday predictions about a Trump presidency all seem to hinge on the idea that the US president will be given absolute power, which we all know he won’t get,” said Sangam, a 32-year-old public relations executive.

Trump – who campaigned against free-trade, immigration, and globalisation – on Sunday accused Singapore as being among a handful of Asian countries that were taking away jobs from the US.

Before his election, Trump had said he would kill the landmark Trans Pacific Partnership free trade deal – of which Singapore is a key proponent.

In his congratulatory message, Singapore premier Lee compared the New York businessman’s electoral victory to Britain’s shock vote to exit the European Union in June.

“Mr Trump’s victory is part of a broader pattern in developed countries – reflecting a deep frustration with the way things are, and a strong wish to reassert a sense of identity, and somehow to change the status quo,” he wrote.