Speaker Paul Ryan (R-Wis.) says the Iran deal negotiated by the Obama administration is likely to remain in place.

"A lot of that toothpaste is already out of the tube. I never supported the deal in the first place. I thought it was a huge mistake, but the multilateral sanctions are done," Ryan said in an interview with NBC's "Meet the Press" airing Sunday.

Most Republicans strongly criticized the deal, warning it doesn't go far enough in ensuring that Iran does not develop nuclear weapons.

"I don't think you're going to go back and reconstitute the multilateral sanctions that were put in place," Ryan said.

The lawmaker maintained that the U.S. should "expend our effort where it can pay off the most," while not ignoring the numerous transgressions with Iran.

"And that's why I think what they're doing now does make a lot of sense. So I think the key is to rigorously enforce this deal," he said.

"But also, remember, they're testing ballistic missiles. They're still the largest state sponsor of terrorism in the world. Human rights abuses galore. And so those are where I think we also need to ratchet up sanctions," he said.

When asked if he was concerned that Iran would retaliate, Ryan said that the U.S. is "appeasing [Iran] already."

"But look what they were doing, we're appeasing them already. So it couldn't get worse," Ryan maintained.

Ryan also disagreed with the notion that Russia is a similarly destabilizing force in the region.

"Nobody holds a candle to Iran's destabilization. So I think - I don't think you can equate those two," he said.