Iran’s Foreign Ministry described the talks as "intensive and lengthy" in a post on X, saying the meetings allowed both sides to present their positions and concerns.
"It was a good start, but its continuation depends on consultations in our respective capitals and deciding on how to proceed," the government account said.
It added there was broad agreement on continuing the negotiations, though decisions on timing, format and the next round will be made following consultations in the two capitals, with Oman continuing to serve as the intermediary.
Araghchi said Sunday that Iran views its nuclear program as a legitimate right and is seeking recognition of that position through negotiations.
"I believe the secret of the Islamic Republic of Iran’s power lies in its ability to stand against bullying, domination and pressures from others," he said, according to Press TV.
"They fear our atomic bomb, while we are not pursuing an atomic bomb. Our atomic bomb is the power to say no to the great powers," the top diplomat added. "The secret of the Islamic Republic’s power is to say no to the powers."
President Donald Trump has expanded the U.S. military presence in the Middle East, deploying the USS Abraham Lincoln carrier strike group and the USS Michael Murphy, a guided-missile destroyer.
Other U.S. naval assets, including the USS Bulkeley, USS Roosevelt, USS Delbert D. Black, USS McFaul, USS Mitscher, USS Spruance and USS Frank E. Petersen Jr., are positioned across key waterways surrounding Iran, from the eastern Mediterranean and Red Sea to the Persian Gulf, Gulf of Oman and Arabian Sea.