Obama delivering remarks after meeting with Filipino President Benigno Aquino alongside the APEC summit in Manila. Thomson Reuters MANILA, Philippines — President Barack Obama lashed out Wednesday at Republicans who insist on barring Syrian refugees from entering the US, deeming their words offensive and insisting "it needs to stop."

"Apparently they're scared of widows and orphans coming into the United States of America," Obama said.

Mocking GOP leaders for thinking they're tough, Obama said overblown rhetoric from Republicans could be a potent recruitment tool for the Islamic State group.

He insisted that the US process for screening refugees for possible entry into the US was rigorous and said the US didn't make good decisions "based on hysteria" or exaggerated risk.

"We are not well served when in response to a terrorist attack we descend into fear and panic," the president said.

Obama's comments during a meeting with Filipino President Benigno Aquino marked his harshest condemnation yet of Republicans' response to the Paris attacks blamed on ISIS that killed 129 people last week.

Republicans in Congress and on the 2016 presidential trail have urged an immediate closing of America's borders to Syrian refugees, but the Obama administration has shown no sign of backing off its plans to bring an additional 10,000 Syrians fleeing civil war into the US.

A Syrian refugee holding his newborn baby as he arrives on a raft on the Greek island of Lesbos. Alkis Konstantinidis Obama took particular ire at a proposal by GOP presidential candidate Jeb Bush to admit only Christian Syrians. Bush later clarified he wanted to give preference to Christians but not exclude properly vetted Muslims. Still, Obama said the idea of allowing only Christians in amounted to "political posturing" that ran contrary to American values.

In Congress, House Speaker Paul Ryan and Senate Majority Leader Mitch McConnell have urged at least a temporary halt in the resettlement of Syrians.

Obama pointed out that he had been waiting a year and a half for Congress to take up a new war-powers resolution to address the ISIS threat, questioning their newfound haste to solve the purported threat of innocents fleeing war.

Defending his administration's screening program, Obama said it took 18 to 24 months to clear a refugee for entry, following vetting by the US intelligence community and other agencies as well as biometrics.

Though there are indications that one of the attackers on Friday carried a Syrian passport and may have arrived in France alongside refugees, Germany's top security official has said the passport might have been a fake intended to stoke fears.

Still, Obama acknowledged that the US public was concerned about attacks on the homeland, noting that Paris "reminds us of home."

"I understand why Americans have been particularly affected," he said.