A brief handshake may be the most likely outcome from preliminary diplomatic talks set for Saturday between American and Iranian officials.

It would probably be enough to keep the discussions going, and potentially lead to the first official face-to-face negotiations between the two countries since President Trump abandoned a landmark nuclear accord seven years ago.

The talks, scheduled to be held in Oman, will serve as a feeling-out session to see whether the Trump administration and Iran’s clerical government could move to full negotiations to limit Iran’s nuclear program.

Both sides come in with high distrust, given that Mr. Trump walked away from the 2015 accord that Iran had brokered with the United States and other world powers, and slapped harsh sanctions on Tehran during his first term.

Mr. Trump now wants to strike a deal — both to showcase his negotiating skills and to keep simmering tensions between Iran and Israel from escalating into a more intense conflict that would further roil the Middle East. Iranian officials are skeptical but “ready to engage in earnest and with a view to seal a deal,” Foreign Minister Abbas Araghchi wrote in The Washington Post this week.

The goals of Saturday’s meeting are modest, reflecting the gap between the two sides: to agree on a framework for negotiations and a timeline. It is not clear whether the envoys will speak directly, as Mr. Trump has insisted, or pass messages through Omani intermediaries shuttling between rooms, as Mr. Araghchi has indicated.