New Delhi, May 23 -- The pathway to permanent residency in the United States or Green Cards could become significantly more difficult for thousands of South Asian and other immigrants currently living and working here because of a newly announced immigration policy.

The memorandum from the U.S. Citizenship and Immigration Services (USCIS) announced on May 22 could mark one of the most consequential procedural changes to the employment-based immigration system in recent years, much like the $100,000 H1B fee announcement last year.

The memo reiterates what the USCIS describes as the "original intent" of immigration law: foreign nationals seeking lawful permanent residence should generally pursue immigrant visa processing through U.S. cons...