President Donald Trump said Wednesday that the United States would hold nuclear talks with Iran next week, teasing the possibility of a deal even after boasting that recent US strikes had crippled the Islamic republic's atomic program.

Trump credited the unprecedented US attacks with the "total obliteration" of Iran's nuclear capabilities, and said they had set the country's program back "decades."

But leaked US intelligence cast doubt on that assessment, saying the strikes had likely delayed Tehran by just a few months.

Before the agreement of a ceasefire on Tuesday, Israel had pounded Iranian nuclear and military sites over the course of 12 days of war, while Iran launched waves of missiles at its regional arch foe in their deadliest-ever confrontation.

The United States joined the fray in support of its ally, hitting two nuclear facilities with massive bunker-buster bombs over the weekend, while a guided missile from a submarine struck a third.

"They're not going to be building bombs for a long time," said Trump, adding the strikes had set back the program by "decades" and that the ceasefire that he declared was going "very well."

He later told reporters that Israel and Iran were "both tired, exhausted," going on to say that talks were planned with Iran "next week."

"We may sign an agreement. I don't know," he added. "I mean, they had a war, they fought, now they're going back to their world. I don't care if I have an agreement or not."

Iranian President Masoud Pezeshkian had said on Tuesday his country was willing to return to negotiations over its nuclear program, but that it would continue to "assert its legitimate rights" to the peaceful use of atomic energy.

'Still early'

Israel's military said Wednesday it was "still early" to assess the damage the war caused to Iran's nuclear program.

"I believe we have delivered a significant hit to the nuclear program, and I can also say that we have delayed it by several years," said Israeli military spokesman Effie Defrin.

Iran's foreign ministry spokesman Esmaeil Baqaei acknowledged to Al Jazeera that its "nuclear installations have been badly damaged, that's for sure."

But US media on Tuesday cited people familiar with a Defense Intelligence Agency report as saying the American strikes did not fully eliminate Iran's centrifuges or enriched uranium stockpiles.

The strikes sealed off entrances to some facilities without destroying underground buildings, according to the report.

Israel had said its bombing campaign, which began on 13 June, was aimed at preventing Iran from acquiring a nuclear weapon, an ambition Tehran has consistently denied.

'The same intensity'

Israeli Prime Minister Benjamin Netanyahu, in an address to the nation after the ceasefire, announced that "we have thwarted Iran's nuclear project."

"And if anyone in Iran tries to rebuild it, we will act with the same determination, with the same intensity, to foil any attempt," he said.

Iranian lawmakers on Wednesday voted in favor of suspending cooperation with the United Nations' nuclear watchdog, state TV reported.

"The International Atomic Energy Agency, which refused to even marginally condemn the attack on Iran's nuclear facilities, put its international credibility up for auction," parliament speaker Mohammad Bagher Ghalibaf said, according to the broadcaster.

The decision to suspend cooperation with the IAEA still requires the approval of the Guardian Council, a body empowered to vet legislation.

In an interview with the Al Araby Al Jadeed news outlet, Iranian Foreign Minister Abbas Araghchi said attacks on Iran's nuclear facilities would have "serious and profound repercussions" on the country's future.

He said Iran remained committed to the Non-Proliferation Treaty but that it had failed to "protect us or our nuclear program", adding without elaborating that Iran's approach towards the non-proliferation regime "will undergo changes."

'Finally, we can sleep'

While Iran and Israel have been locked in a shadow war for decades, their 12-day conflict was by far the most destructive confrontation between them.

Israeli strikes hit nuclear and military targets — killing scientists and senior military figures — as well as residential areas, prompting waves of Iranian missile fire on Israel.

Tehran remained relatively quiet on Wednesday, with many shops still shuttered and only some restaurants open, though there was more life on the streets than during the peak of the war.

"Thank God, the situation has improved, the ceasefire has been reached, and people have returned to work and their lives," said one resident, a 39-year-old salesman who gave his name as Saeed.

Others, however, were uncertain whether the peace would hold.

"I really don't know... about the ceasefire but honestly, I don't think things will return to normal," 28-year-old Amir, who fled Tehran for the Caspian Sea coast, told AFP by phone.

Some Israelis, meanwhile, welcomed the truce.

"Finally, we can sleep peacefully. We feel better, less worried, for the kids, for the family. And I hope it stays that way," said Yossi Bin, a 45-year-old engineer in Tel Aviv.

Israeli strikes on Iran killed at least 627 civilians and wounded more than 4,800, according to the health ministry.

Iran's attacks on Israel killed 28 people, according to official figures and rescuers.

by Alice Chancellor with Payam Doost Mohamadi in Tehran and Danny Kemp in The Hague