Vice President JD Vance tempered expectations set by Donald Trump that the Strait of Hormuz will be 'permanently toll-free.'

Speaking with CNBC on Monday morning, Vance said the permanence of the 'toll-free' strait is still under discussion. 

'Our expectation is that the strait is going to be opened in a toll-free way for the long term, and that’s the sort of thing that we’re going to figure out in these technical negotiations,' Vance said, hedging slightly at Trump's assertion.

His comments appear at odds with Trump's claim that the strategic waterway through which a fifth of the world's oil supply flows will be open for free transit. 

Vance also alluded to a surprise appearance by the President at the signing ceremony of a memorandum of understanding between the US and Iran later this week.

The memorandum to extend the current ceasefire with Iran is expected to be signed on Friday in Geneva. Trump has said that the deal is 'complete' and that the US blockade on the Strait of Hormuz will end.

Iranian officials have said that a peace deal framework is 'close' but have not confirmed that the deal will be signed on Friday.

'I think we’re still figuring out the logistics on who’s going to attend that signing ceremony,' Vice President JD Vance said on Sunday. 'I certainly plan to be there, but it’s possible the President himself could be there.'

Typically, the US Secret Service recommends against the VP and President traveling abroad at the same time due to security concerns, though there has not been any confirmation from the White House that Trump will go to Geneva.

Should the President wish to attend the ceremony, his team may have to scramble to redo the Republican's schedule, as he is supposed to attend the Group of Seven meeting in France this week before returning to the US mid-week. 

It is possible that if Trump wishes to attend the ceremony in Geneva on Friday, he could extend his stay in Europe several days so that he would not have to return to the US for a day before returning to the continent.

Trump has said since last week that Vance will be leading the US delegation at the signing ceremony. 

Vance also told Fox News on Monday that the MOU had already been signed. 'We already signed the deal digitally yesterday, and there's been no money released and that won't change.'

The Trump administration has for months signaled dozens of times that a peace deal is near at hand. 

Previously, it was reported that a likely signing ceremony in Switzerland was expected on Sunday, though that did not occur, and Vance was spotted at the Ultimate Fighting Championship (UFC) event at the White House on Sunday evening. 

The memorandum of understanding is expected to provide a framework to extend the ongoing US-Iran ceasefire for 60 days as both sides negotiate the details of a lasting peace agreement. 

The White House has stated that any agreement with Iran would include provisions to ensure that Iran does not have a nuclear weapon and the opening of the Strait of Hormuz. 

According to a senior administration official, it would ensure that Iran's nuclear material would be destroyed and removed from the country, and its nuclear enrichment capabilities would be decommissioned.

It would also provide a framework for peace between Israel, Lebanon and Gulf nations. 

Should Iran implement the changes, the US would, in turn, provide performance-based sanctions relief and economic reintegration. 

The exact language of the deal has not been released. 

The White House has been contacted for comment.