By Matt Spetalnick, Jeff Mason and Steve Holland

WASHINGTON (Reuters) -When President Donald Trump sent U.S. bombers to strike Iran’s nuclear sites last weekend, he was betting he could help ally Israel cripple Tehran’s nuclear program while keeping his long-standing vow to avoid entanglement in a protracted war.

Just days later, Trump’s surprise announcement on Monday of an Israel-Iran ceasefire agreement suggests he may have bombed Tehran’s rulers back to the negotiating table.

But a long list of big unanswered questions remains, not least whether any ceasefire can actually take effect and hold between two bitter foes whose years-long “shadow” conflict had erupted into an air war marked by the past 12 days of strikes on each other’s territory.

Also still unknown and unmentioned in Trump’s effusive social media post announcing an imminent “Complete and Total CEASEFIRE” are the terms the two sides have agreed to; whether the U.S. and Iran will revive failed nuclear talks; and the fate of Iran’s stockpile of enriched uranium that many experts believe may have survived the U.S. and Israeli bombing campaign.

"The Israelis have accomplished much of their objectives ... and Iran was looking for an off-ramp,” said Jonathan Panikoff, a former deputy U.S. national intelligence officer for the Middle East. "The U.S. hopes this is the beginning of the end. The challenge is whether there is a strategy for what comes next."

Questions also remain about what has actually been agreed to, even as Trump’s declaration raised hopes for the end of a conflict that has prompted fears of a broader regional war.

There was no immediate confirmation from Israel of a ceasefire deal, and the Israeli military said it had detected missiles launched from Iran towards Israel in the early hours of Tuesday. Four people were killed in a missile strike on a building in Beersheba, Israel's ambulance service said.

Soon after, Trump said the ceasefire between Israel and Iran was "now in effect" and urged both countries to not violate it.

While an Iranian official earlier confirmed that Tehran had accepted a ceasefire, the country's foreign minister, Abbas Araqchi, said there would be no cessation of hostilities unless Israel stopped its attacks.

But that did not stop Trump and his loyalists from touting what they see as a landmark achievement of a foreign policy approach they call "peace through strength."

Trump had endorsed Israel's assessment that Iran was getting close to developing a nuclear weapon, which Tehran has long denied. U.S. intelligence agencies said earlier this year they assessed that Iran was not building a nuclear weapon and a source with access to U.S. intelligence reports told Reuters last week that that view hadn't changed.

IRAN'S CALIBRATED RESPONSE

Trump's announcement came just hours after Iran launched missiles against a U.S. air base in Qatar, causing no casualties, in retaliation for the U.S. dropping 30,000-pound bunker-buster bombs on Iranian underground nuclear facilities over the weekend.

Trump administration officials deemed Iran’s response on Monday to have been calibrated to avoid further escalation with the U.S., according to sources familiar with the matter.

Trump called for talks with Israel and Iran, and a senior White House official said Israel agreed to a ceasefire so long as Iran did not launch fresh attacks. Iran signaled that no further strikes would take place, the official said on condition of anonymity.

Trump spoke directly to Israeli Prime Minister Benjamin Netanyahu, and Vice President JD Vance, Secretary of State Marco Rubio and U.S. special envoy Steve Witkoff were involved in the direct and indirect communications with Iran, the official said. Qatar also helped broker contacts with the Iranians.

Iran was also amenable to the ceasefire because it was in a severely “weakened state,” the White House official said. The Iranians had faced days of Israeli bombardment of nuclear and military sites as well as targeted killings of top nuclear scientists and security commanders.

Trump in recent days had also mused publicly about the prospects for “regime change” in Iran.

Earlier on Monday, three Israeli officials had said their government was looking to wrap up its campaign in Iran soon and had passed the message on to the U.S. but that much would depend on Tehran.

“Now that Trump declared 'world peace,' it will be hard for Netanyahu to publicly contradict him,” said Laura Blumenfeld, a Middle East expert at the Johns Hopkins School for Advanced International Studies in Washington.

TRUMP'S BIG GAMBLE

For his part, Trump's unprecedented decision to bomb Iran’s nuclear sites marked a step that he had long pledged to avoid - to intervene militarily in a major foreign war.

In the biggest and potentially riskiest foreign policy move of his presidency, Trump was betting not only that he could take out Iran’s key nuclear site at Fordow but also draw only measured retaliation against the U.S.

There have been fears that Tehran could respond by closing the Strait of Hormuz, the world’s most important oil artery, attacking multiple U.S. military bases in the Middle East and activating proxies against U.S. and Israeli interests worldwide.

If Trump is able to defuse the Israel-Iran conflict, he may be able to calm the storm of criticism from congressional Democrats and appease the anti-interventionist wing of his Republican MAGA base over bombings that ran counter to his own campaign pledges.

It would also allow him to re-focus on policy priorities such as deporting undocumented migrants and waging a tariff war against trading partners.

But Trump and his aides won’t be able to ignore Iran and the lingering questions it poses.

“Can the ceasefire hold?” asked Dennis Ross, a former Middle East negotiator for Republican and Democratic administrations. “Yes, the Iranians need it and the Israelis have largely now acted against the (Israeli Defence Force's) target list.”

But obstacles remain. “Iran is greatly weakened but what is the future of its nuclear and ballistic missile programs? What happens to its stockpile of highly enriched uranium? There will be a need for negotiations - and these won’t be easy to resolve,” Ross said.

(Reporting by Matt Spetalnick; Additional reporting by Phil Stewart; Editing by Don Durfee and Lincoln Feast.)

Posted by: AAngeles