Donald Trump announced the ban on foreign worker visas would be extended to give Americans priority for jobs.
The US tech sector is likely to be hit hard by President Donald Trump's decision to extend a freeze on most immigrant visas, with critics saying the move could undermine American innovation and leadership.
Mr Trump this week said he would extend the ban through the end of the year and broaden it to include H-1B visas for highly skilled workers, as well as L visas used by companies to transfer their own employees.
The move could deal a blow to Silicon Valley and the rest of the tech sector, which has long relied on skilled immigrants to fill key positions of engineers, data scientists and other jobs in high demand.
While Mr Trump has argued the temporary freeze was aimed at helping US workers facing high unemployment during the coronavirus pandemic, critics said the move would backfire and hurt one of the key segments of the American economy.
The freeze "stands to upend the ability of US employers - in the tech sector and beyond - to hire the men and women they need to strengthen their workforce, repower the economy, and drive innovation," said Jason Oxman, president of the Information Technology Industry Council, a trade group that includes more than 70 companies including Apple, Amazon, Google, Facebook and Microsoft.
"At a critical time for the US economy, it will have a dangerous impact on the economic recovery and growth for years to come."
More about politics
Darrell West, who heads the center for technology innovation at the Brookings Institution, said the announcement was "more about politics than good policy," coming at a time when the White House is feuding with Silicon Valley over social media and other issues.
"Trump's executive order is short-sighted in that it will make it difficult for tech companies, farmers, and the hospitality sector to find the workers they need," Mr West said.
FWD.us, an immigration advocacy group founded by tech executives including Facebook CEO Mark Zuckerberg, also said the order would be counterproductive by limiting immigrants who will contribute to science and technology.
"This is a full-frontal attack on American innovation and our nation's ability to benefit from attracting talent from around the world," the group's president Todd Schulte said.
A senior administration official said the order would affect 525,000 jobs in the US, which is currently reeling from a high unemployment rate caused by the pandemic.
It will affect H-1B visas provided to 85,000 workers each year with special skills, many of them joining the US technology industry, as well as J visas, common for academics and researchers, and L visas used by companies to shift workers.
Mr Trump aides said they want to restructure the H-1B visa program from an annual lottery to a system that gives priority to those foreign workers with the most value.
But a recent Georgetown University study found that the US is struggling to compete for global workers with key skills including artificial intelligence and that without easing immigration "other countries may begin to draw AI talent away from American schools and employers. "
Some tech executives added their own personal stories in countering the administration's arguments.
India-born Google CEO Sundar Pichai said: "Immigration has contributed immensely to America's economic success, making it a global leader in tech."
Susan Wojcicki, head of Google-owned YouTube and the daughter of Polish immigrants, echoed those remarks.
"My family escaped danger and found a new home in America," Ms Wojcicki said on Twitter. "We join Google in standing with immigrants and working to expand opportunity for all."
South African-born Elon Musk, who founded Tesla and SpaceX, said he disagreed with the freeze: "In my experience, these skill sets (of tech workers) are net job creators. Visa reform makes sense, but this is too broad."
Andrew Ng, a British-born Chinese-American computer scientist who heads the online education firm Coursera, said the suspension "is bad for the US, bad for innovation, and will shatter dreams and disrupt lives." He added: "as a former H1B visa holder, my heart goes out to all the families affected."