Sen. John McCain, R-Ariz., said on NBC's "Meet the Press" the Republicans would have to come up with their own plan to replace the controversial Obama policy, which was being implemented through an executive order through the Department of Homeland Security.
"It would have to be challenged in court," said McCain, whose homestate is a hotbed of illegal immigration.
McCain said he was disturbed at what he saw as Obama's "dictating that certain laws will not be enforced."
"That is a rather serious step," McCain said. "It's one thing to say you're not going to challenge a law in court, but I don't recall a time when any president has basically said, we're not going to enforce a law that's on the books."
McCain declined to offer any counter-proposals on immigration, telling NBC that Sen. Marco Rubio, R-Fla., was spearheading the development of a GOP plan for immigration reform. "If the president was really serious maybe he would call him and some of us who have been involved in this issue," he said.
White House adviser David Plouffe told NBC the administration was not ignoring immigration law but was instead establishing enforcement priorities. "This was a decision made by the Homeland Security Department to allow them the discretion to focus our enforcement on criminals, people who pose danger to the communities," he said. "That's really where the law enforcement focus should be."