After finding severe gaps in the United States' refuge vetting process, House Republicans are expected to vote Thursday on a refugee bill that would require the Obama administration to more thoroughly certify Syrian and Iraqi refugees who want to come to the United States.

The legislation, H.R. 4038, the American Security Against Foreign Enemies (SAFE) Act of 2015, would put in place the most robust national security vetting process in history to ensure terrorists are not able to exploit U.S. humanitarian programs and enter the country, according to the Homeland Security Committee.

The secretary of Homeland Security, the director of the FBI, and the director of National Intelligence would be required to "certify before admitting any Syrian or Iraqi refugee into the United States that the individual does not represent a security threat," said Republican Rep. Mike McCaul, the chairman of the House Committee on Homeland Security, who authored the bill with Rep. Richard Hudson.

In response to President Obama's call to accept some 10,000 more Syrian refugees over the next year, McCaul said he conducted a nearly year-long investigation into the counter-terrorism challenges associated with bringing those refugees to the U.S. Part of that investigation involved dispatching a team overseas to determine "whether refugee flows might be exploited by ISIS to conduct attacks in the West."

McCaul noted that it appears as if one member of the Islamic State group was able to sneak into Paris disguised as refugee, and said he found similar holes in the U.S.'s refugee vetting process.

"Now we face a grave challenge alongside our allies in Europe - to ensure we protect our people against emerging threats while living up to our humanitarian obligations. My team has found alarming gaps in the vetting of Syrian refugees at home and abroad, and in this high threat environment, we must take urgent action to keep Islamist terrorists from infiltrating their ranks," he said according to the Office of Homeland Security.

House Democratic leadership met Wednesday to discuss an opposition strategy, and said they believe the majority of Democrats will oppose the legislation over concerns that it would harm the overall refugee program, according to Politico.

"Their bill would immediately shut down refugee resettlement in the Syria and Iraq region and severely handicap refugee resettlement in the future," a senior Democratic leadership aide said.

House Democrats are expected to compromise and negotiate an alternative bill with Republicans, who are determined to vote on the Syrian refugee issue before the House leaves for the Thanksgiving holiday on Thursday.

Democratic leaders like California Rep. Xavier Becerra, the chairman of the Democratic Caucus, and New York Rep. Joe Crowley, the caucus vice chair, said Tuesday that they support enforcing a stricter vetting requirements but do not support halting the program.

Democratic opposition to the refugee program seems more apparent in the Senate, with third-ranking Democrat Chuck Schumer of New York saying a "pause" on refugees "may be necessary," reports The Washington Post. Democratic Sen. Dianne Feinstein of California said Tuesday that "we need to be very careful about Syrian refugee admissions," and Democratic Sen. Joe Manchin of West Virginia wrote President Obama asking him to not allow any more Syrians into the country "unless federal authorities can guarantee with 100 percent assurance they are not connected" to the Islamic State group, reported The Hill.

The White House has sternly defended its vetting process and shown no sign of backing off its plans to bring more Syrian refugees to the U.S.

President Obama, speaking Wednesday morning from the Philippines, said Republicans are apparently "scared of widows and orphans coming into" the U.S., reports Time.

"We are not well served when in response to a terrorist attack we descend into fear and panic. We don't make good decisions if it's based on hysteria or an exaggeration of risks," he added. "I cannot think of a more potent recruitment tool for ISIL than some of the rhetoric coming out of here in the course of this debate. It's counterproductive and it needs to stop."