The executive order signed by Trump on June 22, that had temporarily banned issuing fresh H-1B and L-1 visas till December 31, caused a negative impact to the valuation of Fortune 500 firms equivalent to over USD 100 billion in losses, Brookings Institute said in a report released this week.

The H-1B visa, most sought-after among Indian IT professionals, is a non-immigrant visa that allows US companies to employ foreign workers in speciality occupations that require theoretical or technical expertise. L-1 visa is for internal company transfers.

According to estimates, the order barred the entrance of nearly 200,000 foreign workers and their dependents, Brookings said in a report co-authored by Prithwiraj Choudhury, Indian-American Lumry Family Associate Professor of Business Administration at Harvard Business School; Dany Bahasr from Brookings and Britta Glennon from the University of Pennsylvania.

Noting that the nonimmigrant visas (such as the H-1B and L-1 visas) that were targeted are used by companies to hire or transfer high-skilled immigrants, the report said there is overwhelming evidence documenting that skilled immigration improves firm outcomes such as profits, productivity, production expansion, innovation, and investment.

"Thus, it is plausible that the Trump administration's measures significantly restraining immigration will have lasting negative impacts on American firms, and with it, slow down the post-COVID-19 economic recovery," it argued.

Meanwhile, the American Immigration Council on Thursday said another proposed rule by the Department of Homeland Security limiting the admission periods of foreign students and exchange visitors could devastate US leadership in scientific research and technological innovation.

The proposal would negatively impact American colleges and universities and foreign students seeking a higher education degree in the United States and have long-term effects for the legal immigration system, it said.

A proposed rule by the Department of Homeland Security limiting the admission periods of foreign students and exchange visitors could devastate US leadership in scientific research and technological innovation, it said.

The proposal would negatively impact American colleges and universities and foreign students seeking a higher education degree in the United States and have long-term effects for the legal immigration system, it added.

"This rule threatens to undermine the US' role as a world leader in education and stigmatizes tens of thousands of students based on their country of birth. New costs and bureaucratic barriers will make it more difficult for students and exchange visitors to complete their courses of study in the United States — uncertainty that will inevitably drive talented students from around the world to pursue their studies in other countries,” said Beth Werlin, executive director of the American Immigration Council.

"We already have an appropriate system in place to ensure that international students and exchange visitors comply with the terms of their visas. This proposed rule is unnecessary and would significantly reduce our ability to serve as a destination for the most talented students and exchange visitors from around the world," Werlin said.