President Donald Trump convened a meeting with senior officials in the Situation Room on Friday to make a “final determination” on the possible agreement with Iran that could close one chapter of the war.

The memorandum of understanding, which as of Friday afternoon had still not been signed off on, would mark the most significant diplomatic breakthrough since the United States and Israel began the war on Feb. 28. But the agreement, as is widely believed, would focus on the Strait of Hormuz, while the subject of Iran’s nuclear program would require additional negotiations.