When software engineer Mostafa Jafarzadeh was offered a chance by his company to transfer to its Californian headquarters in the United States late last year, he jumped at the "once-in-a-lifetime opportunity".
But with the order issued by United States President Donald Trump restricting people from seven Muslim-majority countries from entering the US, including Iran where Mr Jafarzadeh is from, he may have to pass up his dreams of going to California, which is "as close as it gets to where all the cool technologies were born".
The 30-year-old, who has been working for an Internet of Things software and services company in Singapore since last June, is pessimistic about the prospects of the ban being lifted before April 1, which is when he is due to apply for his work visa.
Uncertainty has loomed large for other Singapore residents like him, who have been affected by the order. There are no official figures available on how many citizens of Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen are living here and could be affected by the ban.
But The Sunday Times understands that Iranians likely form the largest group, with about 500 who are working and studying here. Other groups, such as Iraqis, are possibly much smaller in number, with Iraqi expatriates estimating that they number less than 50 here.
Under the new US order, people from these countries are barred from entry to the US for at least 90 days, since Jan 27, when the order was issued. But last Friday, a Seattle federal judge put a nationwide block on the executive order.
It remains a waiting game for those affected by the travel ban. Some academics said that they will have to put on hold plans to attend conferences in the US. Other citizens from the affected countries had to postpone plans to see family.
While the executive order is being implemented by the US Embassy here, embassy spokesman Camille Dawson told The Sunday Times that the US Department of Homeland Security and State Department "may, when in the national interest, issue visas or allow entry to nationals of countries for which visas and entry are otherwise blocked under this executive order".
She added that the two departments are working closely to identify exceptions to this executive order and will provide additional details when they are available.
American Randy Olsen, 39, had planned to relocate to the US this month with his Iraqi-born wife, who obtained her green card after a two-year process. On Wednesday, he told The Sunday Times that he had contacted the US Embassy here and is waiting to hear back from them about whether they can go ahead with their plans.
Iranian research fellow Amir Hosein Sakhaei, 31, a PhD holder in mechanical engineering from the National University of Singapore who works here, said he is "sad about the racist executive order".
As a research scientist working in academia, he travels to the US about once a year to attend conferences.
"When you find something new in my field, it's very important that you can present it to others. The majority of conferences are in the US," he said.
Mr Jafarzadeh, who frequently meets clients in the US and now cannot go on work trips there, also has similar worries about its impact on his position at work.
While Emirates airline said that it has made "necessary adjustments" to its crewing to comply with the latest US requirements, several Singaporean organisations interviewed by The Sunday Times said that they are largely unaffected.
Singapore Airlines said that it has no crew members who are from the affected seven countries.
On concerns about whether US visa applications for Singaporeans will be affected, Ms Dawson said there has been no change in the availability of visas or the Visa Waiver Programme for Singaporeans.
She added that the US Embassy in Singapore "treats all Singaporean travellers equally, regardless of ethnic or religious background", when it comes to assessing applications.
•Additional reporting by Melody Zaccheus