'SPASM OF RHETORIC'

Speaking in Manila after meeting with Canada's prime minister, Obama said America had always been open to allowing people from war zones to find refuge in the United States, where they become "part of the fabric of American life".

Denouncing the "spasm of rhetoric" over refugees, Obama said refugees already faced the most vigorous vetting process for anyone admitted to the country. He added that "the idea that somehow they pose a more significant threat than all the tourists who pour into the United States every single day just doesn't jibe with reality."

The White House had said Obama would veto the House bill because it would introduce "unnecessary and impractical requirements" that would hamper efforts to help some of the world's most vulnerable people without providing meaningful additional security for Americans.

Comey said there was no credible threat of an attack on US soil similar to the one in Paris, but his agency is monitoring dozens of people it has deemed "high-risk" for copying the attack.

Islamic State militants released a video on Thursday threatening the White House with suicide bombings and car blasts. The threat came a day after another video from the militant group that suggested New York was a potential target.

Ben Carson, a leading 2016 Republican presidential candidate, likened Syrian refugees to "a rabid dog running around your neighborhood," and said admitting them would put Americans at risk.

Some Democrats touted a different approach, promising legislation in the Senate to tighten a visa waiver program that intelligence experts say can be exploited by Islamic State militants or others planning US attacks.

Honduras said on Wednesday it had detained five Syrians seeking to reach the United States for traveling on doctored Greek passports, but authorities in the Central American country said the men did not belong to "any terrorist cell" and four were college students.

The US Department of Homeland Security said members of two Syrian families - two men, two women and four children - turned themselves in to US authorities in Laredo, Texas, on the Mexican border. There was no evidence the Syrians had any connection to terrorism, US officials said.