As President Donald Trump’s envoys gear up for another go at diplomacy with Iran, a major question hovers over their efforts: do the officials they’re communicating with have the juice to make a deal?

It’s not entirely clear to American officials whether the regime figures receiving their messages — which have been passed along by Pakistan and Turkey — have the ultimate authority to sign-off on any peace agreement, let alone implement one, US and Gulf officials said.

So far, Trump appears willing to test the relative power of his new Iranian interlocutors, who no one in the administration is willing to identify publicly. Even as Tehran has called the US’ 15-point proposal to end the war “unrealistic” and as Trump amasses troops in the region, the president says talks are going well and has cast new negotiators as “more reasonable.”

Still, it remains unclear whether this indirect back-and-forth, which could eventually produce in-person talks, will spur Iran to make concessions it was unwilling to make before the war. Some in the Iranian regime are distrustful of the US after earlier rounds of diplomacy were scuttled by American attacks, according to one source familiar with the situation.

And now, with most of the regime knocked out, there’s uncertainty around who would make the final decision about any deal to end the war.

“No one can tell anyone today that whomever shows up to Islamabad has the power for the Iranian regime,” said one regional source, referring to the Pakistani capital that’s a rumored potential location for eventual in-person talks between the US and Iran.

American and regional sources said the Trump administration has been indirectly exchanging messages with Iranian Foreign Minister Abbas Araghchi and Parliament Speaker Mohammad Bagher Ghalibaf, the latter being seen by officials as someone — potentially the only one — who could have influence with new Supreme Leader Mojtaba Khamenei.

But the administration continues to cast a wide net for officials to speak with given the uncertainty around who is making decisions in the Iranian regime, four regional sources said.

When top security Iranian official Ali Larijani was killed by an Israeli airstrike about two weeks ago, it led to even more questions about who was in charge. Regional and US officials had viewed Larijani — who was part of the Iranian negotiating team — as within the inner-circle and someone who could reliably engage on behalf of the regime’s decision-makers, whomever they may be.

So diminished are the upper ranks of Iran’s Islamic government that even the second options for many positions were taken out as part of the joint US-Israeli war that began a month ago.

“The one regime was decimated, destroyed, they’re all dead. The next regime is mostly dead,” Trump said Sunday night on Air Force One. Now, the president said, Iran has moved onto a “third regime” that US officials are indirectly negotiating with, calling them “a whole different group of people.”

Complicating matters is the unknown status of Mojtaba Khamenei. Top American officials have said publicly they believe he is wounded or even dead, though Iranian officials insist he is alive and in charge. He hasn’t been seen or heard since he was elevated to supreme leader after his father was killed, and communicates only through written statements.

“No one has seen him. No one has heard from him,” Secretary of State Marco Rubio said on Al-Jazeera on Monday. He said the regime structure in Iran is “very opaque right now. It’s not quite clear how decisions are being made.”

Mediators from Pakistan and Turkey are also running into difficulty communicating with Iranian officials, since they are often away from phones or devices for long stretches, hunkered down to avoid being killed.

“It is not easy to get response in a short time from that country, so more time has to be afforded as a prerequisite for dialogue down the line,” said a source familiar with the ongoing efforts.

Those communication challenges have only aggravated doubts among US officials about who has real authority in Tehran. Still, officials inside the administration insist the negotiations are real, if preliminary, and that Trump remains hopeful for a deal.

“At the end of the day, we have to see these people end up being the ones in charge, seeing if they’re the ones that have the power to deliver. We’re going to test it,” Rubio said in a separate interview on ABC News, adding that the US has to be ready for the “probability” that those in charge are not more reasonable than the regime leaders before the conflict.

The secretary of state conveyed some of the administration’s thinking on talks with Iran, including uncertainty around the decision-makers, to his counterparts at a Group of 7 meeting in France last week, according to people familiar with the conversations.

So far, both sides are privately taking the talks seriously, even if an in-person meeting doesn’t appear likely this week, US and regional officials said. Trump’s envoys Steve Witkoff and Jared Kushner have been leading the American diplomatic efforts, and Vice President JD Vance could represent the US at potential talks if they materialize, officials have said.

Yet there remains a deep lack of trust in some elements of the Iranian regime that the US is negotiating in good faith, given what happened before the onset of the conflict: a string of meetings that appeared to yield progress, only for Trump to approve a massive round of airstrikes.

A subset of regime figures remains opposed to negotiations, given that history, the person familiar with the situation said. That group doesn’t want to be fooled again by Trump, particularly as he sends additional American troops into the region and issues threats against Iran’s civilian infrastructure.

The White House on Monday downplayed Iran’s pessimistic response to its 15-point proposal, which the foreign ministry called “unrealistic, illogical and excessive.”

“What is said publicly is, of course, much different than what’s being communicated to us privately,” press secretary Karoline Leavitt told reporters. She added later that “these folks are appearing more reasonable behind the scenes privately in these conversations than perhaps some of the previous leaders, who are now no longer on planet Earth.”

Some regional players believe Iran’s decision to green light a higher number of vessels to pass through the Strait of Hormuz was a signal that Tehran wants to set conditions for talks, even if they haven’t replied to the full US proposal. The stranglehold on the key waterway has caused a spike in oil prices.

But even if both sides more actively engage in negotiations soon, regional sources expect an overall agreement is far from being reached.

“Whoever shows up, high level or low level, we don’t expect these issues to be resolved in a few weeks,” the regional source added. “The diplomatic track is quite complex and it will take a long time.”

Interested parties are floating some proposals that strictly focus on safe passage through the strait, one source said, without addressing the larger war. The expectation is that any potential agreement on that front would be separate from an overall US-Iran deal, the source said, describing such a plan as a short-term “confidence building-measure.”

While Trump pushes for a deal, his military operation has continued apace. The White House said Monday that 11,000 targets had been struck over the course of the war and 150 naval vessels had been sunk.

According to the administration’s early estimations, the war was expected to last between four and six weeks, meaning the window for ending it has now opened. Leavitt restated that planned timetable Monday.

Yet Iran continues to fire missiles and drones toward its neighbors and keep the Strait of Hormuz in a stranglehold. It also retains nearly 1,000 kilograms of highly enriched uranium believed to be buried deep underground. While the White House insists the regime is increasingly eager to make a deal, others in the region see a different reality.

“They want to take their time,” the regional source said, calling Iran’s ability to snarl the strait “a big factor” in its calculations.

And despite the ongoing military operations, the Iranian regime remains highly ideological, and therefore unlikely to easily bend.

“You’re dealing with people who are 10 times worse than Hamas,” that source said.