US Republicans, defying president, propose tightening Syrian refugee screening

House Republican lawmakers defied President Barack Obama on Wednesday and laid out plans to tighten screening of Syrian refugees after the Paris attacks, in a political fight that challenges the U.S. view of itself as a refuge for downtrodden immigrants.

Concerned about possible strikes against the United States after Islamic State killed 129 people in the French capital on Friday, the Republican chairman of a House of Representatives security committee proposed additional scrutiny of refugees fleeing Syria or Iraq seeking to enter the United States.

The White House quickly threatened a veto, saying the measure "would unacceptably hamper our efforts to assist some of the most vulnerable people in the world."

Both the House and Senate would have to approve the legislation for it to get to Obama. Some Senate Republicans appeared to split from their House counterparts, saying there may be more effective ways to secure the country.

Reports that at least one Paris attacker may have slipped into Europe among migrants registered in Greece prompted several Western countries to question their willingness to take in refugees.

Under the House legislation, no refugees from war-torn Iraq or Syria could enter the UnitedStates until several top-level U.S. security officials verify that they do not imperil national security.

Americans are "uneasy and unsettled" over the events in Paris, said House Speaker Paul Ryan, a Republican.

"We are a compassionate nation. We always have been and we always will be. But we also must remember that our first priority is to protect the American people," Ryan said.

At an Asia-Pacific summit in Manila, Obama accused Republicans of "hysteria and exaggeration of risk" in trying to make it more difficult for refugees to enter the United States.

"Slamming the door in the face of refugees would betray our deepest values. That's not who we are. And it's not what we're going to do," Obama wrote later on Twitter.

Obama stood by a plan the White House announced in September to admit 10,000 Syrian refugees within a year.

Refugees from the four-year-old Syrian civil war who seek U.S. entry already undergo a rigorous screening that takes between 18 and 24 months.

VISA WAIVER PROGRAM

Some Senate Republicans said they were more concerned about the U.S. visa waiver program, which allows millions of foreigners to visit the United States every year without any screening.

"The visa waiver program potentially is the place where there's greater gaps possibly than the refugee program itself," Bob Corker, Republican chairman of the Senate Foreign Relations Committee, told reporters after a classified briefing from Obama administration officials.

Democratic Senator Dianne Feinstein said she and Republican Jeff Flake hoped to introduce legislation on Thursday tightening the visa waiver system. Their measure would bar anyone who has been in Syria for the past five years from entering the United States under the waiver program.

The House could vote as soon as Thursday on the bill proposed by Michael McCaul, Republican chairman of the House Homeland Security Committee. House Republican leaders said they expected the measure would pass, although some of the party's most conservative members threatened to join Democrats who opposed it.

Some conservatives backed an amendment that would put a six-month moratorium on admitting refugees. Others said the bill did not specifically cut off funding for refugee resettlement.

The Paris attacks have hardened rhetoric on the U.S. presidential campaign trial.

Republican candidate Jeb Bush called for an increased U.S. troop presence on the ground in Iraq as part of a global coalition to take on Islamic State. His comments could lead to comparisons to the 2003 U.S.-led invasion of Iraq ordered by his brother, former President George W. Bush.