Vice President JD Vance arrived in Switzerland this week as the Trump administration’s most visible defender of a fragile Iran memorandum of understanding, even as officials moved to tamp down reports of internal concern over whether Tehran can be trusted to follow through on nuclear concessions.

"If it doesn’t happen, I’m blaming JD Vance. If it does happen, I’m taking full credit," joked President Donald Trump this month of the Memorandum of Understanding (MOU) with Iran.

The MOU, signed last week, has not resolved the core dispute over Iran’s nuclear program, but instead opened a 60-day negotiating window aimed at turning broad commitments into enforceable terms — leaving Vance to defend a framework that supporters call a diplomatic opening for sustained stability in the region and skeptics fear could give Tehran room to stall.

While Secretary of State Marco Rubio, Secretary of War Pete Hegseth and CIA Director John Ratcliffe have been central to previous high-profile foreign policy missions, Vance spent last week as one of the administration’s chief public advocates for the Iran deal, repeatedly fielding questions about the negotiations during a media blitz for his new book.

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A senior U.S. official told Fox News Digital earlier this month that there was a "split" inside the administration on support of the Iran MOU but wouldn't say which officials did not support the decision. The talks have been fragile for weeks, with the MOU serving less as a breakthrough than a temporary framework while U.S. officials continue to wrestle with whether Iran can be trusted to follow through on nuclear commitments.

CIA Director John Ratcliffe reportedly emerged as a key intelligence leader who expressed doubt about the intelligence behind the Iran deal to Trump and other senior officials, Axios reported. Rubio and Hegseth also reportedly held reservations, while Vance and other officials advocated for the MOU, according to the outlet. 

The CIA did not comment when asked by Fox News Digital if Ratcliffe was skeptical about the deal.

A second senior U.S. official told Fox News Digital that Trump officials were all aligned in supporting the deal and viewed it as the appropriate path forward.

While a White House official added that Vance emerged as a lead negotiator because Trump tasked him with the role from the outset, arguing his position as vice president gives him the stature to bring key players from countries such as Qatar and Pakistan to the negotiating table.

When asked about the reports of an alleged "split," the White House fired back that the MOU meets all the previous requirements expressed by the administration and the president would only sign a "good deal."

"President Trump listens to all opinions on any given issue — but everyone understands he is the final decisionmaker," a White House official told Fox News Digital.

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While Ratcliffe has historically kept a more reserved role as CIA chief, Rubio and Hegseth have embraced the spotlight repeatedly during high-level missions, hosting press briefings and posting on social media – even sharing memes surrounding major policy wins. 

Rubio has publicly backed the MOU, but his support has been noticeably more restrained than his advocacy for past foreign policy efforts. The secretary has reposted clips of the deal signing and Vance's media appearance discussing Iran, but has not directly made a statement. His latest post on X was congratulating Colombian President-Elect Abelardo De La Espriella on his victory.

Rubio was also part of the president’s delegation in France at the G7, seen standing behind him during Trump’s sideline presser on the deal. Rubio did not make any comments during the press conference.

Hegseth also has remained active on social media during the NATO summit, posting updates on alliance-related meetings and highlighting various War Department initiatives, while notably refraining from commenting directly on the Iran agreement.

His last public remarks directly addressing U.S.-Iran relations came more than a month ago on May 5 during a Pentagon briefing alongside Caine. Hegseth discussed Project Freedom, which was a strike against Iran's nuclear infrastructure – separate and distinct from Operation Epic Fury.

Since then, Hegseth's public appearances have focused largely on NATO and defense diplomacy, including bilateral meetings with foreign counterparts and engagements with leaders from Italy, Singapore, South Korea and Ecuador.

READ IT: THE FULL TEXT OF THE US-IRAN MEMORANDUM OF UNDERSTANDING

The framework has come under fire from conservatives and liberals alike who have drawn comparisons to former President Barack Obama’s JCPOA, a politically toxic benchmark for many Republicans that the president and Vance have rejected in public remarks.

During an appearance on Fox News' "The Five" last week, Vance argued the JCPOA comparison stems from a misconception because the proverbial carrot-and-stick positions from the Obama-era deal have been reversed.

The Pentagon doubled down on their backing of the Iranian deal when asked by Fox News Digital if there were any doubts.

"Of course, Secretary Hegseth supports the Peace Deal with Iran and all of President Trump’s objectives," Chief Pentagon Spokesperson Sean Parnell told Fox News Digital when asked if there was any friction about the Iran agreement.

State Department spokesperson Tommy Pigott offered Fox News Digital administration a similar statement backing the Iran deal.

"Secretary Rubio and the entire administration is 100% in lockstep behind President Trump. The President has taken unprecedented action to prevent the Iranian regime from obtaining a nuclear weapon, making the U.S. and the entire world safer," Pigott said.

Rubio is heading to Geneva Monday after Vance has already been engaged in discussions with Iranians alongside Jared Kushner and Steve Witkoff since Sunday.

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Rubio, Hegseth and Ratcliffe have previously been at the center of some of the Trump administration’s most significant foreign policy engagements and achievements, from high-stakes talks with Vladimir Putin in Alaska to G7 summits and NATO conferences.

Vance’s absence from Trump’s January Mar-a-Lago announcement following the capture of former Venezuelan President Nicolás Maduro drew notice at the time, particularly as Rubio, Hegseth, Ratcliffe, Joint Chiefs Chairman Gen. Dan Caine and senior adviser Stephen Miller appeared alongside the president for the administration’s victory-lap moment.

Fox News Digital reached out to the Office of the Vice President for comment.

Vance stayed late into the night Sunday evening to push the deal to the finish line in an attempt to get nuclear inspections to start as soon as possible.

"It's funny, we were trying to call some of the inspectors last night around two in the morning. As you can expect, not many people are answering their phone at two in the morning," said Vance Monday.

"I expect that will happen at the minimum this week, but we think even some of those conversations with the inspectors and with the IAEA could happen as soon as today," Vance added.

Fox News Digital's Charles Crietz contributed to this report.