The fast-track processing of H-1B work visas has been temporarily suspended, according to the United States Embassy in Singapore.
These visas are in hot demand around the world among skilled professionals, especially those working in the tech sector.
Premium processing for applications was suspended on Monday, possibly for up to six months but there have been no announced changes to normal processing times and "no expected changes to wait times for visa interviews or visa process times", US Embassy Singapore spokesman Camille Dawson said.
She noted that there are two parts to H-1B processing: An applicant's petition must first be approved by the US Citizenship and Immigration Services Agency (USCIS). Then the State Department processes the visas for those applicants from outside the US.
The H-1B programme allocates 85,000 visas a year and they are quickly snapped up, mostly by tech firms looking for talent from across the world.
Number of H-1B1 visas allocated to Singapore per year
Number of H-1B visas issued to Singaporeans in 2015
Number of H-1B1 visas issued to Singaporeans in 2015
Another work visa programme - the H-1B1 - which is available to Singaporeans and Chileans as part of their countries' free trade agreements with the US, does not require applicants to get USCIS approval.
This means the suspension of premium processing will have no impact on the availability of visa interviews for H-1B1 applicants, Ms Dawson said.
Under the trade deals, 5,400 professionals from Singapore and 1,400 from Chile can enter the US each year for work under the H-1B1 programme.
In 2015, there were 333 H-1B visas and 551 H-1B1 visas issued to Singaporeans, according to data provided by the US Embassy.
The USCIS also said this week that it will step up scrutiny of H-1B visa petitions during site visits, including when it cannot validate the employer's basic business information or firms that have a high ratio of H-1B workers compared with local staff.
The new measures, which are being implemented to detect "fraud and abuse", do not appear to affect the H-1B1 visa programme.
"This announcement regarding the site visit isn't really new. Site visits have been happening since 2009. Site visits target H-1Bs. H-1B1 is not targeted," Ms Suhi Koizumi, a San Francisco-based immigration lawyer, told The Straits Times yesterday. The tighter rules on skilled immigration have not deterred Singaporeans from wanting to work in the US.
Mr James Tan, managing partner of Quest Ventures, a US venture capital firm, said: "If one qualifies for the visa, why wouldn't it be worth it to stay on, especially in tech and in the Bay Area? While the visa is important, its cost nonetheless pales against the opportunities and costs of living in the US."