The latest exchange of fire has thrown into doubt the shaky truce between Iran and the United States that is intended to allow talks to bring an end to the four-month-old war.

Here’s what happened the last time U.S. and Iranian negotiators held indirect talks.

Sources familiar with the last round of talks in Doha, said negotiators for the two countries spent two days discussing maritime traffic in the Strait of Hormuz and unfreezing Iran’s funds.

There were no signs of a headway toward a lasting peace, however.

The Doha discussions ​produced “positive progress” on issues related to the memorandum that halted the war in June and were “building on the outcomes” of ⁠a summit in Switzerland, the ministry spokesperson said in a post on X.

Trump said the two sides were making progress ​on possible limits to Iran’s nuclear program- the main reason he launched the war along with Israel in February.

But the sources said the nuclear program did not come up in the talks, which were technical in nature.

U.S. Vice President JD Vance said that matter would be addressed later. “Obviously, we’re worried about the nuclear issue, we’re going to start talking about that,” he told reporters.