There is "bipartisan skepticism" about the nuclear deal that has been reached with Iran, Sen. Bob Corker (R-Tenn.) said during an appearance on "Fox News Sunday."
The accord, which would temporarily freeze Iran's nuclear activities, would span six months while more lasting framework was developed.
But Corker, the ranking member of the Senate Foreign Relations Committee, said he was worried that the agreement doesn't require Iran to stop enriching uranium entirely, and he wouldn't rule out the idea of supporting further sanctions.
"I think you're going to see on Capitol Hill again a bipartisan effort to try to make sure this is not the final agreement because people know this administration is long on announcements, but very short on follow through, and I think there's a lot of concern," he said.
Asked if he saw the current deal as a window of opportunity, Corker said he worried the Iranians were making the same calculation.
"From their perspective, they do view this administration as weak," Corker said. "And I think from their standpoint, they see this as their window of opportunity to negotiate with an administration that has shown that it really doesn't have a lot of the intestinal fortitude that other administrations have had. They've seen that in Syria, and it's been a learning experience for them."
Also speaking on Fox, Sen. Ben Cardin (D-Md.) expressed worries as well.
"We are very concerned as to whether Iran will live up to even these commitments, and this is the first step," said Cardin, who also sits on the Foreign Relations Committee.
Cardin said the temporary deal should not be allowed to stand permanently.
"That would not be acceptable to the Congress not the American people and I hope the international community," Cardin said. "I think Congress will be watching this very closely. We will not stand by and let this be the final deal."