Iranian President Masoud Pezeshkian declared Sunday that Tehran would rebuild its nuclear sites “stronger than before,” following Israeli and American strikes that targeted key facilities.

“By destroying buildings... we will not be set back,” Pezeshkian said in a video posted to his official website, as quoted by AFP, adding that Iranian scientists still possess the necessary nuclear expertise.

In June, Israel launched an unprecedented bombing campaign against Iran, targeting nuclear and military infrastructure. The US later joined in, hitting Iran’s key nuclear sites.

US President Donald Trump stated that the strikes “obliterated Iran’s nuclear program”. Iranian Foreign Minister Abbas Araghchi later acknowledged that the damage was “serious and severe,” following the US announcement of a halt in fighting.

Pezeshkian’s comments coincided with renewed diplomatic efforts between the US and Iran. Oman, which has served as a key intermediary between Tehran and Washington, urged both sides to resume negotiations.

“We want to return to the negotiations between Iran (and) the United States,” said Omani Foreign Minister Badr Albusaidi at the IISS Manama Dialogue conference in Bahrain.

Tehran and Washington held five rounds of indirect nuclear negotiations, mediated by Oman, which ended following the 12-day air war in June.

Iranian government spokeswoman Fatemeh Mohajerani confirmed Sunday that Tehran “has received messages” regarding the resumption of diplomacy, though she did not provide further details.

Araghchi declared Saturday that the Islamic Republic has no intention of engaging in direct negotiations with the United States over its nuclear or missile programs, and will continue enriching uranium.

“We will never negotiate our missile program, and no rational actor would disarm. We cannot stop uranium enrichment, and what cannot be achieved by war cannot be achieved through politics,” Araghchi told Al Jazeera.

While rejecting direct talks, Araghchi said Tehran is open to indirect negotiations. “We are ready to negotiate to remove concerns about our nuclear program and are confident in its peaceful nature. Reaching a fair agreement is possible, but Washington has proposed unacceptable and impossible conditions,” he added.

He also condemned the reactivation of the “snapback” sanctions mechanism, calling it illegal. The sanctions, reimposed in September, followed failed negotiations between Iran and the E3 countries - Britain, France, and Germany - who triggered the “snapback” mechanism in the 2015 nuclear deal.