South Carolina senator Lindsey Graham on Thursday blasted the Trump administration's reported decision to cut a CIA program that trained and armed Syrian rebels fighting the Bashar al-Assad regime.

The president's call to end the controversial Obama-era program reflects a broader desire to bolster cooperation with Russia, the Washington Post reported. Graham said he was mystified by the decision.

“I’m totally blindsided by it. I think most of us in Congress are,” Graham told THE WEEKLY STANDARD. “This is a major change in policy—maybe they have a good reason for it, but I don't see it.”

The Trump administration has seized on working with Russia to defeat the Islamic State (ISIS) in Syria, where U.S. and Russian priorities have traditionally been at odds: Russia has long insisted that Syrian leader Bashar al-Assad remain in power, while America has pushed for his ouster.

On that point, though, members of the Trump administration have wavered and suggested that Assad’s removal is not a top priority. Secretary of State Rex Tillerson also told reporters earlier this month that U.S. and Russian objectives in Syria are "by and large ... exactly the same."

Graham described the decision to scrap the program as a surrender to the Kremlin and a boost for Iran.

“This is what Putin has been asking for for years,” he said. “It is a betrayal of the people we’ve tried to help. It is a capitulation to Russia and Iran and Assad. … It is a strategic mistake. It puts our Arab allies in a bad spot. It diminishes our standing.”

“Other than that, it’s a good idea,” he remarked.

Wisconsin congressman Mike Gallagher also strongly disapproved of the decision along similar lines.

“If reports are accurate, we are all but abandoning Syria to Assad and his enablers in Russia and Iran,” he said. “Far from advancing American interests, this would embolden our adversaries, deflate our allies, and greatly exacerbate tensions in an already volatile region.”

“As we learned during the last administration, bad things happen when we outsource our foreign policy to our adversaries," he continued. "Assad, Russia, and Iran do not share our interests, and it’s a dangerous fantasy to think that they can play a constructive role in Syria."

Still, the 2013 program has attracted criticism, especially early on. Critics noted that some CIA-backed groups fought alongside extremists, in effect doing their work for them, and U.S.-provided weapons at times ended up in the wrong hands. Some fighters also defected to extremist groups.

“The insurgents were far more friendly to the extremists than people wanted to admit,” said Thomas Joscelyn, a senior fellow at the Foundation for Defense of Democracies.

He stressed that the “moderate opposition” is not a monolith with a single chain of command, but a series of often disjointed factions.

"Factions deemed 'moderate' often weren't really moderate at all—one can be an extremist without being a member of al-Qaeda or ISIS," he said.

Defenders saw the program, at the least, as a symbol that the United States remained devoted to Assad's ouster. Some also viewed it as a bargaining chip in negotiations with Russia. If the program is to be cut, as the Post reported, it shouldn't be "for free."

Graham indicated he wouldn’t be on board with scrapping the program even if it was in exchange for something from Russia.

“I’m not into the ‘exchanging with the Russians’ deal. Not in Syria,” he said.

Washington and the Kremlin brokered a ceasefire along Syria’s southwest border in early July. The Post reported that the president decided to cut the program roughly a month ago and that it was not a condition of the ceasefire. Trump has said there could be a second ceasefire in the future.

Illinois congressman Adam Kinzinger warned broadly against working too closely with the Kremlin.

“It is dangerous. Vladimir Putin does nothing in the human interest, it’s all in his interest,” he said.

Kinzinger said he wanted to get to the bottom of why the administration cut the program.

“I’m interested if there’s more to the story than what we know, but the base of it—it was very depressing to see,” he said. “We need to know why it happened, and we play a significant role in oversight.”

A House Foreign Affairs committee aide also told TWS the panel is asking the administration for more details on the decision.