The American Civil Liberties Union (ACLU) on Saturday praised a Seattle-based federal judge's order temporarily blocking President Trump's executive order denying entry to the U.S. for citizens of seven Muslim-majority countries.

"This ruling is another stinging rejection of President Trump's unconstitutional Muslim ban," said Omar Jadwat, the director of the ACLU's Immigrants' Rights Project. "We will keep fighting to permanently dismantle this un-American executive order."

The ACLU was among a coalition of legal groups to file a lawsuit on behalf of two Iraqi refugees who were detained at New York's Kennedy International Airport shortly after Trump signed the executive order on Jan. 27.

That lawsuit prompted a federal judge in New York to block part of the president's executive order, preventing authorities from deporting people from the seven targeted countries who arrived in the U.S. after the order had been signed.

That ruling did not amount to a full swipe at the constitutionality of Trump's executive action.

But the biggest challenge to the order to date came on Friday, when federal Judge James Robart in Seattle issued a stinging rebuke of the president's immigration action, effectively ordering the government to cease any efforts to enforce it.

Trump delivered a fiery response to the ruling on Saturday, tweeting that Robart's opinion was "ridiculous" and warning that it would be overturned. Robart was appointed by former President George W. Bush and approved by the Senate in a 99-0 vote in 2004.

"The opinion of this so-called judge, which essentially takes law-enforcement away from our country, is ridiculous and will be overturned!" Trump tweeted.

A spokesperson for the Department of Homeland Security said in a statement on Saturday that it had suspended "any and all" actions implementing the travel ban.

"At the earliest possible time, the Department of Justice intends to file an emergency stay of this order and defend the President's Executive Order, which is lawful and appropriate," spokesperson Gillian Christensen said.