Rep. Jerry Nadler, D-N.Y., said Monday that President Trump was wrong to issue an executive order temporarily banning immigrants from Muslim-majority countries because American citizens are the real terrorism threat in the U.S.

"The real threat here so far is home-grown, American terrorists, and not people from these seven countries," Nadler said on CNN.

Trump on Friday issued an order suspending immigration from Iraq, Iran, Libya, Syria, Somalia, Sudan, and Yemen. The 90-day ban is meant to give federal agencies time to review the information they need to verify the identity of immigrants seeking to enter the United States.

It also shut down the refugee program for four months, and indefinitely suspended acceptance of Syrian refugees.

Democrats and even some Republicans have said the order goes too far, but Trump's team has said the temporary ban is needed in the face of terrorism threats that some immigrants could pose to U.S. citizens.

A federal court has already stopped one part of Trump's plan that calls for the deportation of some immigrants. Nadler predicted Trump's entire order would fall in the courts.

"I think the courts will stop it," he said.