NEW YORK

 People who reject refugees because they are Muslims are the best allies of Daesh and other terrorist groups, the UN’s refugee chief said Monday.

Antonio Guterres' remarks at a UN Security Council meeting on Syria came in the wake of U.S. Republican presidential hopeful Donald Trump's proposal to ban all Muslims from entering the country.

While acknowledging the possibility that terrorists could try to infiltrate refugee movements, Guterres said those fleeting warzones cannot be blamed for a threat "which they're risking their lives to escape".

"Those that reject Syrian refugees because they are Muslims are the best allies in the recruitment propaganda of extremist groups," he said.

On Saturday, Democratic presidential candidate Hillary Clinton also said Trump's remarks were becoming Daesh's "best recruiter".

"They are going to people showing videos of Donald Trump insulting Islam and Muslims in order to recruit more radical jihadists," Clinton said during a televised debate among leading Democratic candidates.

Front-runner in the polls ahead of the Republican primaries in 2016, Trump called for a complete ban on Muslims entering the U.S. in the wake of the San Bernardino attack in which 14 people were killed by two suspected Daesh sympathizers.

His statement has been largely condemned both in the U.S. and worldwide.

"We must not forget that, despite the rhetoric we are hearing these days, refugees are the first victims of such terror, not its source," Guterres said.

The Syrian civil war has made the country the world's single-largest source of refugees and displaced people, as more than 4.3 million Syrians are now refugees and at least 7.6 million have been internally displaced, according to UN figures.

Neighboring Turkey, which is now the largest refugee-hosting country, has spent nearly $8 billion caring for more than two million Syrian refugees on its soil.