Senate Minority Leader Chuck Schumer (D-N.Y.) on Sunday vowed to fight President Donald Trump’s executive order that blocked the entry of Syrian refugees and imposed a ban on travelers coming from several Muslim-majority countries.

“This order was mean-spirited and un-American,” the senator said as he fought back tears during his weekly press conference in New York City.

“The president wants people to believe that everyone’s a terrorist or a criminal who’s an immigrant. It’s not fair and it’s not right.”

Standing alongside refugees from Iraq and Syria, whose families were affected by the ban, Schumer argued the travel ban would make America less safe by hurting its counterterrorism programs at home and abroad. He said Senate Democrats were preparing legislation aimed at overturning it.

“We’re demanding the president reverse these executive orders that go against what we are, everything we have always stood for,” Schumer said.

Schumer noted that his middle name, “Ellis,” refers to Ellis Island, the early 20th-century gateway for immigrants to the United States.

“This fight’s in my bones. It’s on my birth certificate,” he said.

Late Saturday night, two federal judges halted parts of the order, temporarily prohibiting the government from immediately deporting refugees who have been cleared by authorities to enter the country. The Department of Homeland Security, however, issued a statement Sunday maintaining it would continue enforcing the order, likely ensuring a legal battle over its scope.

Schumer told reporters on Sunday that he believes the courts ultimately will step in and strike down the order as unconstitutional. Until such time, however, he said he hopes more Republican lawmakers in Congress join with Democrats to pass legislation to reverse it.

“If we get a few more Republicans, I think we can pass legislation to overturn it. I think it’ll be up to the Republicans,” he said.

Very few Republicans in Congress have voiced their opposition to the order so far. Sen. Rob Portman (R-Ohio) said Sunday that it was “not properly vetted” and welcomed its halt. Senate Majority Leader Mitch McConnell (R-Ky.) warned against implementing religious tests, but he stood by the order.

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