President Barack Obama's administration announced on Wednesday that it had eased some immigration rules to allow more of the millions of Syrians forced from their homes during the country's three-year civil war to come to the United States.
Only 31 Syrian refugees - out of an estimated 2.3 million -were admitted in the fiscal year that ended in October, prompting demands for change from rights advocates and many lawmakers.
Hundreds of thousands of Syrians have been taken in by neighboring countries such as Jordan, Lebanon and Turkey.
The rules changes granted exemptions on a case by case basis to the "material support" bar in U.S. immigration law, according to an announcement in the Federal Register signed by Secretary of State John Kerry and Jeh Johnson, the Secretary of Homeland Security.
That bar had made it impossible for anyone who had provided any support to armed rebel groups to come to the United States, even if the groups themselves receive aid from Washington.
The advocacy group Human Rights First said, for example, that the existing law had been invoked to bar a refugee who had been robbed of $4 and his lunch by armed rebels, and a florist who had sold bouquets to a group the United States had designated as a terrorist organization.
"These exemptions will help address the plight of Syrian refugees who are caught up in the worst humanitarian crisis in a generation," Illinois Senator Richard Durbin, chairman of the U.S. Senate subcommittee on human rights, said in a statement.
It was not immediately clear how many Syrians would be affected by the rules change.
By early January, 135,000 Syrians had applied for asylum in the United States. But the strict restrictions on immigration, many instituted to prevent terrorists from entering the country, had kept almost all of them out.
Washington has provided $1.3 billion in humanitarian assistance to aid Syrian refugees. This year, the United Nations is also trying to relocate 30,000 displaced Syrians it considers especially vulnerable. Witnesses at a Senate hearing last month had testified that Washington would normally accept half.