Following last week’s historic meeting between President Donald Trump and Syrian President Ahmed al-Sharaa at the White House, experts say the U.S. must remain highly wary of the new Syrian leader, who was previously an al-Qaeda affiliated terrorist leader.

The November 10 meeting marked the first time a Syrian leader had come to Washington, and Trump left the meeting praising al-Sharaa, who rose to power in December of last year after the rebel alliance he led toppled the dictatorial regime of Bashar al-Assad. “We want to see Syria become a country that’s very successful,” Trump remarked. “And I think this leader can do it, I really do.”

Al-Sharaa, who formerly lead the Islamist militant group Hay’at Tahrir al-Sham and was imprisoned by U.S. forces during the Iraq war as a member of al-Qaeda, has since sought to present himself as a moderate in seeking a partnership with the U.S. So far, al-Sharaa’s government has gotten off to a shaky start as it has failed to secure much of Syria’s vast territory beyond Damascus and the surrounding region, with Islamic State (IS) terrorists continuing to launch numerous attacks. In addition, al-Sharaa’s security forces attempted to contain clashes between the minority Druze and local Bedouin clans in the southern city of Sweida in July, but instead reportedly participated in the killings of hundreds of Druze civilians. Members of the security forces accused of the crimes have since been detained.

Nonetheless, al-Sharaa has convinced the Trump administration to lift a series of U.S. sanctions that had been in place to counter Assad’s former reign of terror. The U.S. Treasury Department instituted a six-month suspension of economic sanctions under the Caesar Act, which “fell short of Syrian requests that the sanctions be fully repealed.” The State Department also removed al-Sharaa from a global list of designated terrorists. The actions follow a series of sanctions that were lifted in June. As noted by The Washington Post, the lifting of the sanctions “will allow Syria to access international finance, reconnect with the global banking system and import goods to help reconstruct its decimated health care system and other sectors.”

Lawmakers like Senator Lindsey Graham (R-S.C.) say that al-Sharaa’s government needs to be given time in order to determine whether or not it can be trusted.

“[T]he question is, have we replaced an Iranian-controlled government with [an] al-Qaeda type government?” he asked during “This Week on Capitol Hill” over the weekend. “That’s the question. Or is it something we can tolerate and live with? [Syria] joined the anti-ISIS coalition … and Israel is worried about their borders. They attack Druze and other groups in the south. It’s a work in progress. We’ll see if this guy can deliver. But the question is, will this new government under al-Sharaa be run in a way to protect religious minorities, or will it become a radical Sunni state? Time will tell.”

Graham went on to acknowledge that there are “a lot of reasons to be concerned” about Syria’s new leader.

“Israel is negotiating border security between Syria and Israel,” he explained. “They’re creating a corridor, we hope, so that Israel can help the Druze, who are a religious minority, if they are ever attacked again. Christians in Syria could be the next target of these Islamists. There [are] some people around [al-Sharaa] that are hopeful. There [are] some people around him that are just hard terrorists. The president’s decided to try to give the guy a chance. I’m willing to give him a chance. But you’ve got to have a provision to snap back sanctions if he doesn’t deliver.”

Family Research Council President and former U.S. Commission on International Religious Freedom (USCIRF) Chair Tony Perkins argued that the Trump administration should require al-Sharaa to establish a track record of protecting religious minorities before lifting sanctions.

Graham concurred. “Give him some guidelines, some protection of religious minorities, breaking away from the corruption and things that are measurable, that are real, that would make a difference and reward good behavior but have hanging over their head sanctions coming back if they fail,” he observed. “I think if you don’t do that, it will be a mistake.”

Perkins went on to note that while the White House has lifted administrative sanctions on Syria, it will be up to Congress to decide whether further sanctions should be revoked.

“We have a provision in the [National Defense Authorization Act] that basically sets conditions that they have to meet,” Graham agreed. “If they don’t, you have a snapback provision. I think the House will probably want that. I think we will give relief under the Caesar Act … but there will be snapback provisions. Because if we don’t, then we don’t really have a whole lot of leverage. Maybe this guy is a diamond in the rough, or maybe it’s just more of the same. Syria is strategic for Israel. Their neighbor, the Golan Heights, was captured by Israel. It was used in a bunch of wars to attack Israel. They’ll never give the Golan Heights back to Syria. So I worry about Israel’s borders. But if they can prove they’re going to go after ISIS and al-Qaeda and not be like those guys and they can work a deal with Israel protecting Israel’s borders, then they should get rewarded.”

“Trust but verify,” Perkins observed. “Amen to that,” Graham responded. “And it applies here in spades.”