What does an Iran nuclear deal have to do with ISIS?

Sen. Marco Rubio (R-FL) delivers remarks during the graduation of small business owners from the Goldman Sachs 10,000 Small Businesses program held at the Freedom Tower at Miami Dade College on February 9, 2015 in Miami, Florida.

Joe Raedle, Getty Images

One senate Republican -- and potential GOP presidential candidate -- is charging that the White House played a political game with the administration's draft authorization for the use of military force (AUMF), treating it as a bargaining chip in nuclear negotiations with Tehran.

Sen. Marco Rubio, R-Florida, accused the administration of using a light touch on its request for war powers against ISIS because a deal with Iran hangs in the balance.

"I believe that much of our strategy with regards to ISIS is being driven by a desire not to upset Iran so that they don't walk away from the negotiating table on the deal that you're working on. Tell me why I'm wrong," Rubio challenged to senior national security officials during a Senate Foreign Relations Committee hearing Wednesday morning.

"Because the facts completely contradict that," Secretary of State Kerry retorted. He went on to warn that the sensitive nature of the negotiations would not allow him to discuss specifics during the hearing.

Negotiations with Iran, which are expected to continue until the end-of-March deadline for an agreement outline, have been difficult and drawn out for the State Department -- and the process has opponents suggesting the Obama administration simply doesn't understand the middle eastern power.

"So they're supportive of more ground -- if the U.S. sent more military personnel into Iraq as trainers, advisers, logistical support, they would support that? Iran would support that? Rubio pressed Kerry.

"Well, they're not going to come out and openly support it," the secretary of state replied. "And they obviously would be nervous about it. But they're not going to object if that's what it is."

"Are you telling us that [war against ISIS] is a non-factor in terms of how it would impact negotiations?" the Florida senator asked. "Or is that something you can't discuss in this setting?"

Kerry, a former senator and Foreign Relations committee chairman, pushed back.

"No, they would welcome our bombing additionally ISIS, actually. They want us to destroy ISIS; they want to destroy ISIS. ISIS is a threat to them; it's a threat to the region," Kerry fired back. "And I think you're misreading it if you think that there isn't a mutual interest with respect to [ISIS] between every country in the region."

The nuclear talks with Tehran have been tense and the subject of partisan bickering.

Just this week, Arkansas Sen. Tom Cotton, along with 46 other Republicans in the Senate, sent a letter to Iranian leaders, cautioning that any nuclear deal -- even though it's being negotiated by the White House -- would live or die by the legislative branch. And anything short of a ratified treaty, the letter asserted, would be a much weaker "executive agreement."

"The next president could revoke such an executive agreement with the stroke of a pen," GOP senators wrote, "and future Congresses could modify the terms of the agreement at any time."

The White House is indeed striking a delicate balance in the region, attempting to wage a war against ISIS with the backing of an Iranian militia while simultaneously negotiating a deal to neuter Tehran's nuclear capabilities.

"[The letter] does come at an inappropriate time," White House spokesperson Josh Earnest said of the GOP letter in a briefing Wednesday. "That attempting to sandbag the president of the United States in the midst of negotiations that he's engaged in--not just with Iran but with our international partners--is not just unprecedented but inappropriate. It does undermine the president's ability not just to conduct foreign policy but to advance our national security interests around the globe."

Several other administration-backers have condemned the Republicans' letter, and even former Secretary of State Hillary Clinton took to Twitter to castigate Cotton's actions.

"GOP letter to Iranian clerics undermines American leadership. No one considering running for commander-in-chief should be signing on," Clinton said in a tweet Wednesday.

Kerry, for his part, was unequivocal in his stance that the U.S. war strategy should not be misconstrued as a play to appease Iranian leaders.

"What's important, Senator, with respect to your question is to understand this, and I think this has been a misread by a lot of people up here on the Hill, to be honest with you: There is no grand bargain being discussed here in the context of this negotiation," Kerry said, wrapping up his response to Rubio. "This is about a nuclear weapon potential. That's it. And the president has made it absolutely clear they will not get a nuclear weapon."