Samantha Vinograd is a CNN national security analyst. She served on President Barack Obama's National Security Council from 2009 to 2013 and at the Treasury Department under President George W. Bush. Follow her @sam_vinograd . The views expressed in this commentary are her own. View more opinion articles on CNN.

As tensions with Iran ratchet up, the need to identify lines of direct communication is increasing. While officials in Iran contend with their own internal politics, they are also probably trying to determine whether President Donald Trump is a man of his word when he says that the United States is prepared to talk to the regime. His history of capriciousness when it comes to deal-making and deal-breaking -- coupled with a perception that no one is really empowered to speak on his behalf -- is probably giving the Iranians even more pause as they publicly and perhaps disingenuously lay out avenues for de-escalation.

Of course, Trump isn't the only potential obstacle. Just like in the United States, there is one true commander in chief in Iran, Supreme Leader Ayatollah Khamenei, and he's thus far refused Trump's offers to talk. If Trump is intent on a near-term tensions truce and a longer-term nuclear negotiation, he must convince the Supreme Leader that taking a chance on the US, again, isn't a fool's errand.

Break bad habits

Revisiting and restarting nuclear negotiations would require credibility and patience, two things Trump isn't exactly known for. Because he's tarnished American credibility by backing out of the Iran deal, the Iranians are probably wary that the US signing on the dotted line will last beyond Trump's latest mood swing. The Joint Comprehensive Plan of Action, known as JCPOA, took years of careful negotiations, first behind the scenes and then publicly, to hammer out. New nuclear negotiations would take time, even when experts have been empowered to hammer out difficult details.

But the Iranians know their audience, and it's an audience of one. Kim Jong Un just had to send Trump a letter to get him to jump from threatening fire and fury to falling in love, and everyone knows that Trump responds to public displays of affection. It is probably no accident that Iranian Foreign Minister Mohammad Javad Zarif floated a potential deal with the US in front of reporters. His offer to ratify the JCPOA Additional Protocol in exchange for the lifting of US sanctions isn't much, substantively, because Iran is already observing the additional protocol. But the public nature of his offer is probably geared toward grabbing the President's penchant for negotiating and posturing in front of the media -- and may be an opening salvo in trying to give Trump something that he can say he got from Iran.

Message in a bottle

Though the United States may be eager to curb Iran's accelerating nuclear activities, the President needs to do something out of character and speak with his intelligence community about the source of Iran's latest offer for a deal. Zarif floated this offer, but it's unclear whether he speaks on behalf of the Supreme Leader or the Iranian Revolutionary Guard Corps.

The Supreme Leader holds all the reins of power in Iran -- including control of the military -- and he, Iranian President Hassan Rouhani and Zarif have been on different pages in the past. Zarif even tendered his resignation -- which was rejected -- after months of pressure with hardliners in the Iranian government and after he was excluded from meetings with Syrian President Bashar al-Assad. As Iran's primary negotiator with during the Iran deal negotiations, he probably took a lot of flak for the US withdrawal and re-imposition of sanctions.

Just like Trump doesn't mind throwing his own team under the bus, the Supreme Leader has publicly chastised Rouhani and his team (including Zarif) for crossing red lines during negotiations and more recently for the implementation of the nuclear deal . Any message from Zarif and Rouhani to negotiate must be assessed against Khamenei's disdain and distrust of the United States.

Paul's peace offering

Although Trump has said that former US Secretary of State John Kerry acted illegally by speaking with Zarif, the President initially said he knew nothing about Kentucky Sen. Rand Paul's engagement with Zarif. However, a day later, Trump confirmed that Paul is involved in diplomatic talks with Iran.

JUST WATCHED Trump: US 'destroyed' an Iranian drone Replay More Videos ... MUST WATCH Trump: US 'destroyed' an Iranian drone 01:22

Paul is not known for his diplomacy within the US government, let alone with hostile foreign powers, and he has no known history with or special knowledge of Iran. The State Department has taken the lead in past negotiations with Iran, and it's unclear with whom Paul is coordinating within the executive branch, other than perhaps Trump. Zarif may view Paul as a tempering influence over Trump -- Paul's been on record opposing intervention in Iran -- and a useful interlocutor in that regard.

But the confusing cacophony of other US government voices on Iran may leave the Iranians wary of engaging with anyone but Trump, if they really do want to de-escalate. Other Trump allies in Congress, like South Carolina Sen. Lindsey Graham , have warned about an overwhelming US military response against Iran. Within the executive branch, it's hard to keep track of who has the latest instructions from the President. National Security Adviser John Bolton has made policy statements on Iran that have differed from the President's, including when he said the US would stay in Syria and fight Iran.

The President has called his own intelligence community extremely passive and naive when it gave its public assessment of threats from Iran. He attributed his decision to call off strikes against Iran on last-minute input from the Department of Defense, rather than his own change of heart.

Stay up to date... Sign up for our new newsletter. Join us on Twitter and Facebook

Trump's ever-changing policies toward Iran are also a cause for confusion. His initial diatribes that the Iran deal was a failure because it covered only nuclear weapons, not other activities like ballistic missile development, have now shifted to his saying that he wants to talk with Iran just about nuclear weapons.

US officials will need to look at who's talking when it comes to assessing Iranian offers to talk. Because the Iranians are probably distrustful of Trump and unclear whether anyone is authorized to actually speak on behalf of him, factions within the Iranian power structure may try to appeal to Trump's preference for publicity and float superficially substantial offers that he can use to back down. But, if we're really serious, the President will have to break some bad habits and clearly identify someone to speak on his behalf publicly and, more important, behind the scenes, where the real action happens.