Senior American and Iranian officials held talks through intermediaries in Oman this past week, the first such conversations since Iran launched a retaliatory attack on Israel with hundreds of missiles and drones last month, according to a person familiar with the recent meetings.

Brett McGurk, the top White House official on Middle East policy, and Abram Paley, the deputy special envoy for Iran, attended the talks in Oman. The goal was to try to get Iran, which supplies weapons and training to militias across the Middle East, to move to rein in its partners. Since the Israel-Hamas war broke out, several Iran-backed militias in Iraq and Syria have stepped up attacks on American troops, raising fears of a wider war.

The most powerful of the regional militias, Lebanon-based Hezbollah, has been exchanging fire with the Israeli military in northern Israel and southern Lebanon. However, U.S. intelligence officials assess that neither Hezbollah nor Iran wants to engage in a wider war.

The United States has had no diplomatic relations with Iran since 1979, and discussions are often conducted through intermediaries and back channels. The format of the talks in Oman was similar to ones held in January: The Americans sat in one room while their Iranian counterparts sat in another, and Omani officials shuttled between the rooms. The new set of talks was first reported by Axios.

Iran carried out the retaliatory attack last month using more than 300 missiles and drones after Israel killed Gen. Mohammad Reza Zahedi, a commander of Iran’s Quds Force, in a strike on an Iranian diplomatic compound in Damascus. Iran equated that to a strike on Iranian soil, and responded with its first direct attack on Israeli territory.

The militaries of the United States and Israel worked with those of several European and Arab allies and partners to foil the assault.

For years, Israel has been striking at Iranian forces and partner militias in Syria, where the government is aligned with that of Iran. That “shadow war” is now an open conflict.

Jake Sullivan, the White House national security adviser, said in a news conference this week that “the threat posed by Iran and its proxies to Israel, to regional stability and to American interests is clear.”

“We are working with Israel and other partners to protect against these threats and to prevent escalation into an all-out regional war through a calibrated combination of diplomacy, deterrence, force posture adjustments and use of force when necessary to protect our people and to defend our interests and our allies,” he added.

Mr. Sullivan was expected to travel to Saudi Arabia and Israel this weekend to discuss issues involving the Israel-Hamas war; a potential broad diplomatic and security deal involving the United States, Saudi Arabia and Israel; and the threat of Iran.