US President Donald Trump announced on Wednesday he had signed an executive order that temporarily suspends the issuance of new green cards in order to protect American jobs amid the coronavirus pandemic.

“In order to protect our great American workers, I have just signed an executive order temporarily suspending immigration into the United States,” Trump said at the daily White House briefing.

“This will ensure that unemployed Americans of all backgrounds will be first in line for jobs as our economy reopens. It will also preserve our health care resources for American patients,” he added.

The order, released shortly after Trump’s remarks, applies to those seeking permanent residence in the United States and will last for 60 days, at which point it will be reevaluated and potentially extended. Trump said Wednesday he could change the order during the 60 days.

The order will apply to foreign nationals seeking a green card who are outside the United States at the time of the order, excluding from the suspension those who are in the country seeking to change their immigration status.

It carves out exceptions for essential workers, including medical personnel, spouses and children of US citizens, members of the Armed Forces, individuals designated by law enforcement, prospective foreign adoptees of U.S. citizens, and prospective "investor visa" users.

Trump noted Tuesday that the order would not apply to seasonal farm workers, who would seek seasonal guest worker visas.

“It could be modified,” he told reporters Wednesday. “Right now, we have a very powerful immigration ban, but it may be modified, meaning made tougher or made less tough.”

Trump initially announced he would freeze legal immigration into the United States in a tweet late on Monday night.

“In light of the attack from the Invisible Enemy, as well as the need to protect the jobs of our GREAT American Citizens, I will be signing an Executive Order to temporarily suspend immigration into the United States!” he wrote.

The death toll in the US from coronavirus reached 47,050 on Wednesday, according to a Reuters tally.

On Tuesday, the number of cases of coronavirus in the United States surpassed the 800,000 mark, according to figures released by Johns Hopkins University.