DUBAI, United Arab Emirates (AP) — A top Iranian security official will travel Tuesday to Oman, the Mideast sultanate now mediating talks between Tehran and the United States over the Islamic Republic’ nuclear program aimed at halting a possible American strike.

Ali Larijani, a former Iranian Parliament speaker who now serves as the secretary to the country’s Supreme National Security Council, likely will carry his country’s response to the initial round of indirect talks held last week in Muscat with the Americans.

Larijani is due to meet with Omani Foreign Minister Badr al-Busaidi, the chief intermediary in the talks, and Oman’s Sultan Haitham bin Tariq, the state-run IRNA news agency reported. IRNA described the talks as “important,” without elaborating on what message Larijani will carry.

Iran and the U.S. held new nuclear talks last week in Oman. Foreign Minister Abbas Araghchi, speaking Sunday to diplomats at a summit in Tehran, signaled that Iran would stick to its position that it must be able to enrich uranium — a major point of contention with U.S. President Donald Trump, who bombed Iranian atomic sites in June during the 12-day Iran-Israel war. That war disrupted earlier rounds of nuclear talks between Washington and Tehran.

Israeli Prime Minister Benjamin Netanyahu is to travel to Washington this week, with Iran expected to be the major subject of discussion, his office said.

The U.S. has moved the aircraft carrier USS Abraham Lincoln, ships and warplanes to the Middle East to pressure Iran into an agreement and have the firepower necessary to strike the Islamic Republic should Trump choose to do so. Already, U.S. forces shot down a drone they said got too close to the Lincoln and came to the aid of a U.S.-flagged ship that Iranian forces tried to stop in the Strait of Hormuz, the narrow mouth of the Persian Gulf.

The U.S. Transportation Department’s Maritime Administration issued a new warning Monday to American vessels in the strait to “remain as far as possible from Iran’s territorial sea without compromising navigational safety.” The strait, through which a fifth of all oil traded passes, is in Iranian and Omani territorial waters. Those traveling into the Persian Gulf must pass through Iranian waters.

Jon Gambrell, The Associated Press