Much remains unknown regarding the progress of Washington’s nuclear talks with Iran, but the head of the U.N. nuclear watchdog, the International Atomic Energy Agency (IAEA), said the international community must "trust but verify" that Tehran is engaging in good-faith negotiations. 

The U.S. and Iran are set to hold a third round of discussions on Saturday, which will deal with the technical aspects of Iran's nuclear program, as well as political negotiations, according to reports. 

IAEA Director General Rafael Grossi has applauded the U.S.-Iran negotiations mediated by Oman, but said the top nuclear agency has not yet been asked to assist in the negotiations, though he has been in communication with Middle East envoy Steve Witkoff. 

US CONFIRMS THIRD ROUND OF NUCLEAR TALKS WITH IRAN AFTER ‘VERY GOOD PROGRESS’

"I think there's a general expectation that this goes well, and that the agreement is verified by the IAEA," Grossi told reporters from Washington, D.C., on Wednesday. "It's good the United States and Iran have a direct conversation. Of course, there are parallel processes.

"We have to keep our eyes on the ball. We must avoid Iran or prevent Iran from getting weapons. This is the objective."

Grossi said that from the perspective of not only the top nuclear agency, but from world leaders he has been in communication with, there is a "degree of expectation" that after the political agreements are hashed out between Washington and Tehran, it will be the IAEA that makes the nuclear terms "credible" and "verifiable."

"They all are expecting the IAEA to step in at the right time," he said. "We are at their service to support, to make this thing credible. In a certain sense, they may have a political agreement, but then we have to make it verifiable." 

IRAN’S LONG TRAIL OF DECEPTION FUELS SKEPTICISM OVER NEW NUCLEAR DEAL AS TALKS CONTINUE

Fox News Digital obtained a copy of an address Iranian Foreign Minister Abbas Araghchi — who traveled to China on Wednesday to reportedly discuss progress in the nuclear negotiations — was set to give at the Carnegie International Nuclear Policy Conference, though he never delivered the address due to format change requests by Tehran that were denied by the host. 

But in his address, he was set to position Iran as a proponent of nuclear non-proliferation and said Iran’s position had been "mischaracterized."

Since the U.S.’ withdrawal from the Joint Comprehensive Plan of Action (JCPOA), which Tehran has argued made the deal mute, Iran has significantly advanced its programs by stockpiling near-weapons-grade-enriched uranium to levels that, if further enriched, could produce five nuclear warheads, as well as its centrifuges and missile capabilities. 

When asked by Fox News Digital if Grossi assessed the Islamic Republic’s position to be honest, he said, "Trust, but verify. We need to verify."

"We are inspectors — that's the only way we build trust," he added. 

Grossi said the administration needs to identify what the end goals of this latest deal will be, as the framework of the JCPOA — widely criticized by Trump — is now very dated due to the advancements Iran has made. 

Issues like uranium stockpiles, inventories, centrifuge advances and weaponization capabilities are all on the table in the U.S.-Iran negotiations. 

"We have a much more complex field in front of us," Grossi warned. "The good thing is we know what we need to look at. We have a unique perspective of that."