Tuesday began as a frantic day of diplomacy in Washington, with Air Force Two ready to fly Vice President JD Vance to Islamabad for another round of peace talks between the US and Iran.

Several hours later, Air Force Two hadn't taken off, and the negotiations were postponed. President Donald Trump announced that he would extend the ceasefire with Iran, set to expire on Wednesday evening, to allow the regime more time to create a "unified proposal" to end the war.

In between, Trump weighed his options as the world waited to see if the countries were any closer to ending the war. Trump's decision marked the second time in as many weeks that he has backed off a threat to escalate the war, buying himself more time to wind down a conflict as it approaches the two-month mark.

Vance never officially announced the Islamabad trip, leaving Washington guessing. And Iran never officially committed to attending the talks, leaving the White House in a difficult position to decide whether to send Vance, with no assurance that Tehran would even come to the table.

As the day wore on, signs of a postponement emerged. Special envoy Steve Witkoff and Trump's son-in-law Jared Kushner, senior members of the US negotiating team led by Vance, flew to Washington from Miami instead of heading straight to Islamabad. Soon after, Vance made his way to the White House for "policy meetings" as the president and his senior advisers debated what to do next.

In the end, Trump announced the ceasefire extension on Truth Social, his preferred means for war updates since it began in late February. The president said he made the decision at the request of Pakistan, which has mediated talks between Tehran and Washington.

"We have been asked to hold our Attack on the Country of Iran until such time as their leaders and representatives can come up with a unified proposal," Trump said.

Notably, Trump this time did not specify how long the ceasefire might last. Earlier this month, he set a two-week deadline for the first ceasefire. That came after conflicting comments in press interviews, during which he said the talks were going well but also warned that he would consider resuming the war if Iran refused to negotiate.

"There is no clear formula" for ending wars, James Jeffrey, a former US ambassador to Iraq and Turkey, told the BBC.

Trump isn't the first US president to "threaten significant military escalation," Jeffrey added, "while also putting a good deal on the table."

Trump's open-ended statement on Tuesday was more measured than his past social media attacks on Iran. That may signal Trump's desire to end a war that has roiled the global economy and is unpopular with anti-interventionist supporters in Trump's Maga base.

"This is a pragmatic decision based on what are quite obvious fractures in the current leadership of the Iranian government," said Brian Katulis, a senior fellow at the Middle East Institute.

But Katulis said Trump's decision also created more uncertainty about how long the war will last.

"This move begs the question though for Trump about how he can deal with the economic pain that Americans are experiencing and the political pain he's experiencing from his base," Katulis said. "He hasn't answered the questions that are still driving this crisis."

With the ceasefire extension, the US and Iran now have more time to make a durable peace deal. But major questions remain.

Iran has said that the US blockade of the Strait of Hormuz is an act of war. While Trump chose not to restart the war immediately, he gave no indication he would end the blockade, which the US hoped would pressure Tehran to back down. So far that hasn't happened, leaving Trump with fewer options other than ramping up the military campaign.

Iran, meanwhile, has not signalled interest in ending its nuclear program or support for proxy groups in the Middle East -- two so-called "red lines" that Trump has demanded be included in any final peace deal.

Trump bought himself more time. But a quick resolution to the war, for now, seems as elusive as ever.