A new US immigration policy could force many green card applicants to leave the country and apply from abroad, disrupting families, careers and long-term settlement plans for Asian workers already facing years-long backlogs for visas.

US Citizenship and Immigration Services said on May 22 that it would only grant “adjustment of status” – the process that allows prospective immigrants already in the US to apply for permanent residence without leaving the country – in “extraordinary circumstances”.

The shift would push most applicants towards consular processing overseas, meaning they may have to leave the US for interviews at embassies or consulates abroad and wait while their cases are processed.

For many immigrants, a green card, officially known as a Permanent Resident Card, is the main route to long-term economic security in the US, granting them the right to live and work in the country indefinitely, with some eventually applying for citizenship after meeting residency requirements.

“The new rules, if implemented, will of course disrupt the plans of hundreds of thousands of families and individuals in the US,” said Russell A. Stamets, who specialises in offering legal advice to people who want to do business in the US and is a partner at the New Delhi-based law firm Circle of Counsels.

He said the revised rules appeared to be having an immediate deterrent effect, regardless of whether the applicants could prevail in any legal challenges.