Senate Democrats said on Sunday that they planned to introduce legislation to overturn President Donald Trump's executive order ending the settlement of Syrian refugees in the United States and temporarily barring nationals from seven Muslim-majority nations from entering the country.

"We're demanding the president reverse these executive orders that go against what we are, everything we have always stood for," minority leader Sen. Chuck Schumer, D-New York, said in a press conference Sunday.

The mixed messaging from the administration around the order has already sown confusion among law enforcement agencies responsible for detaining or deterring people of certain nationalities entering the United States.

The very nature of Trump's executive order is under constitutional scrutiny.

A federal judge has already issued a stay against the executive order that also barred all refugees for entering the country for 120 days. The ruling stopped short of demanding that security officials release all nationals detained at airports and who find themselves in legal limbo.

Sen. Chris Murphy, D-Conn., is reportedly preparing legislation that forces Trump's executive order to comply with the 1965 Immigration and Nationality Act, which makes it illegal to bar immigrants based on national origin. Murphy also plans to capitalize on the fact that at least 10 Republican lawmakers have come out against the travel ban, while more than a dozen have refused to offer full support for it.

"I think ultimately this ban will be struck down by the courts, but we need to put legislation on the table that Republicans could support, that overturns the ban," Murphy told The Washington Post.

The ban has already led to negative reactions from global leaders. Iran has called for a ban on U.S. citizens to that country in retaliation. The Iraqi parliament is debating a similar action.

Trump's executive order is titled "Protection of the Nation From Foreign Terrorist Entry Into the United States." But it should be pointed out that no one in the United States has been killed in a terrorist attack by anyone from any of the seven countries singled out in the order since Sept. 11, 2001.