Washington and Tehran would need to defend any potential deal as a win for their side. And each has a leader whose approach to talks is vexing mediators.

In its latest offer delivered on Sunday, Iran proposed opening the key waterway to shipping traffic and lifting the U.S. blockade, while postponing the thornier nuclear issue until later.

Iran’s foreign minister has already arrived in the country, state media reported. He was believed to be carrying a written response to a U.S. proposal to end the war.

The killing of Ayatollah Ali Khamenei ushered in a new form of collective leadership in the country, with more power for the Revolutionary Guards.

A “whole civilization will die tonight,” the president said as he turned up the pressure on Iran’s leaders to reopen the Strait of Hormuz.

The vote came hours before an 8 p.m. deadline set by President Trump to reach a deal to reopen the waterway.

With President Trump threatening to strike Iranian power plants, some war-weary civilians are panicking over a possible new debacle.

In an online journal, Yousef Pezeshkian offers readers a mix of personal anecdotes and glimpses behind the scenes as Iranian leaders are picked off one after another.

One of Ayatollah Ali Khamenei’s closest confidants, Mr. Larijani emerged as the face of the government after Mr. Khamenei was killed.

The weeklong fight over Iran’s next leader pitted the Revolutionary Guards against moderates. The generals won, but only over spirited resistance.

Revered cultural icons that have withstood the upheavals of history are being hit hard in the war being waged by Israel and the United States.

Officials say Mojtaba Khamenei’s legs were hurt, but the circumstances as well as the extent of his injuries were unclear. He has remained out of view since being announced as leader three days ago.

Many in Iran feel helpless in the face of their entrenched system, and some are becoming increasingly embittered by the fierce American and Israeli bombardment.

Opponents of the government, however, worried the new supreme leader, a son of the recently killed Ayatollah Ali Khamenei, would rule with an iron fist like his father.

The succession of the slain leader’s son is seen as a signal of the Islamic republic’s defiance of Israel and the United States, and of continuity during crisis.

The U.S. and Israel have pounded Iran’s leadership and undercut its defense capabilities, but President Trump has offered wildly different explanations for what he hopes to achieve.

Huge flames erupted into the sky over Tehran and a nearby city on Saturday.

Ali Larijani, the head of Iran’s Supreme National Security Council and a close confidant of Ayatollah Ali Khamenei, said Iran was determined to avenge the killing of the leader.

The C.I.A. has given small weapons to Iranian Kurdish forces in Iraq in a covert program that began before the current war.

If Mojtaba Khamenei is chosen by Iran’s senior clerics, it may signal a victory for hard-liners, an analyst said.