Donald Trump is expected to rescind a policy that protects nearly 800,000 immigrants who entered the United States illegally as children, a senior administration official said on Thursday.

The US president’s decision could be announced as early as Friday, but could also come next week, the official said.

Mr Trump had pledged on the election campaign trail to scrap all of former president Barack Obama’s executive orders on immigration – including the Deferred Action for Childhood Arrivals (DACA), or “Dreamers” program.

What to do about the so-called Dreamers has been actively debated within the White House and Trump administration. One senior administration official described the situation as a “tug of war” between factions in favor of the move and those opposed. Officials, believing the DACA program to be ultimately unconstitutional, want Congress to impose a legislative fix for the Dreamers, two officials said.

US Representative Steny Hoyer of Maryland, the number two Democrat in the House of Representatives, released a statement expressing concern about reports that Trump may terminate the program, saying this would be “devastating” to many Dreamers.

“In the absence of Congress enacting bipartisan immigration reform, which must remain our goal, the President ought to continue providing peace of mind to Dreamers that they need not live in fear of being sent away from the only home many of them have ever known,” Hoyer said.

A brief guide to DACA

– The Deferred Action for Childhood Arrivals (DACA) refers to protections put in place by the last administration for undocumented immigrants who were brought to the US as children during the last 10 years. The number in the programme is 800,000.

– It means that, as the people in DACA get older, they can enroll in college, obtain legal jobs, get a driver’s licence, travel abroad, etc, without worrying about US immigration officials.

In effect, they can come out of the shadows.

– They are commonly refered to as “Dreamers”, because of the Dream Act, which was first introduced in 2001 to offer legal status in return for attending college or joining the US military. It was eventually voted down in the Senate in 2010.

– Each DACA deferral lasts two years - after which one can apply to have it renewed. the deferral can be cancelled if a recipient commits a crime.