Iranian negotiators could view the fresh nuclear deal as a chance to gain an edge over an Obama administration lacking “intestinal fortitude,” according to Sen. Bob CorkerRobert (Bob) Phillips CorkerSanford: GOP lawmakers 'running for cover' over fear of Trump tweets Trump’s trusted diplomat faces daunting task with North Korea George Will says Trump doesn’t inspire ‘cult’ in GOP: ‘This is fear’ MORE (R-Tenn.).

Appearing on “Fox News Sunday,” Corker said that Iran views the president’s team as “weak” and could use the new deal on its nuclear development to win relief from economic sanctions without any major changes to their nuclear program.

“If you see the reaction in Iran right now, they’re spiking the football in the end zone,” said Corker, the top Republican on the Senate Foreign Relations Committee. Sen. Ben Cardin (D-Md.), who also sits on that panel, also emphasized the need to closely watch Iran to make sure they follow through on their end of the deal, but praised the administration’s diplomatic efforts.

“The bottom line is that we have to work with the international community,” he said. “Are we concerned that Iran will try to circumvent this agreement? You bet we’re concerned about that.”

Global diplomats announced late Saturday that they had closed marathon talks with a limited agreement to get control over Iran’s nuclear ambitions. The six-month deal will place limits on that nation’s nuclear capabilities and subject it to closer oversight in exchange for limited relief from global economic sanctions.

Both Corker and Cardin emphasized that the top priority now was ensuring that this interim deal does not become the final one, as both parties have said they will continue talks during that six-month timeframe in efforts to strike a long-lasting deal about Iran’s nuclear program.

“People are very concerned that the interim deal becomes the norm … there’s bipartisan skepticism here,” said Corker. “My greatest concern is seeing follow through … hold their feet to the fire.”

“Congress needs to be prepared … to make sure that this interim step is enforced, that there’s no deviation whatsoever during this period of time,” said Cardin. “Congress, I think will want to make it clear that if Iran does not live up to its commitments…we will have stronger sanctions against Iran.”