President Trump is expected to announce Tuesday that he has decided to terminate the 2012 program that has deferred deportations for people who came to the U.S. undocumented as children and some congressional Republicans are opposing the move.

Retiring Rep. Ileana Ros-Lehtinen, R-Florida, spoke out Sunday on Twitter against Mr. Trump's upcoming announcement about the Deferred Action for Childhood Arrivals (DACA) program.

After teasing #Dreamers for months with talk of his "great heart," @POTUS slams door on them. Some "heart"... — Ileana Ros-Lehtinen (@RosLehtinen) September 4, 2017

In another tweet, Ros-Lehtinen said that if reports about the president ending the program within six months are true, Congress "must work to immediately pass law protecting #Dreamers who only know the US."

Sen. Jeff Flake, R-Arizona, who's up for reelection next year, is also criticizing the move. In an interview on CNN's "State of the Union" on Sunday, Flake was asked why Mr. Trump should go back on his campaign promise to end DACA.

"Because it would be the right thing to do to go back on a promise," Flake said. "Obviously, you hope that presidents keep some of their campaign promises and you hope that they ignore others. This is one that he ought to ignore. There are 800,000 DACA kids, kids who were brought across the border. The median age, I think, is 6 years old for those 800,000 when they came across the border. They should not be punished for the sins of their parents. That's just the basic principle that we ought to follow here."

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Rep. Steve King, R-Iowa, have been among the few Republicans who have spoken out publicly in support of the president.

Ending DACA now gives chance 2 restore Rule of Law. Delaying so R Leadership can push Amnesty is Republican suicide. https://t.co/iYOLxFWp7V — Steve King (@SteveKingIA) September 4, 2017

On Friday, top Republicans Speaker Paul Ryan, R-Wisconsin, and Sen. Orrin Hatch, R-Utah, called on the president to hold off on terminating the program.

"I actually don't think he should do that," Ryan said on Wisconsin radio station WCLO. "And I believe that this is something that Congress has to fix. Let me back up for a second. President Obama did not have the legislative authority to do what he did. You can't, as an executive, write law out of thin air. And so that's very, very clear. We've made that very clear."

Hatch also said Friday, "I've urged the president not to rescind DACA, an action that would further complicate a system in serious need of a permanent, legislative solution."