Reaching the nuclear fuel at the Isfahan facility would not be easy for Tehran, however, an unnamed official has told the agency

Israel believes that US strikes on Iranian nuclear sites last month did not destroy enriched uranium stockpiles at one of the facilities, meaning Tehran could be able to retrieve the nuclear fuel, the AP has reported, citing a senior Israeli official.

US President Donald Trump previously claimed that Tehran's nuclear program had been "completely and totally obliterated" after the US joined Israeli attacks on Iran and bombed the country's Fordow, Natanz, and Isfahan nuclear facilities on June 22. He was backed by CIA Director John Ratcliffe, who told lawmakers last month that several key sites had been destroyed and would take years to rebuild. Tehran maintains that its nuclear program is purely civilian and not intended to create a weapon.

According to Israeli assessments, deeply buried stocks of enriched uranium at Iran's Isfahan facility are "potentially retrievable," the AP reported on Friday.

However, a high-ranking official who talked to the news agency stressed that accessing the nuclear fuel underground "would take a very difficult recovery effort" by Tehran.

Unlike the Fordow and Natanz facilities, Isfahan was not targeted by American "bunker-buster" bombs during the attack, reportedly only being struck by Tomahawk missiles.

Israel also does not give credence to media reports claiming that Iran had moved its enriched uranium to an undisclosed, safe location ahead of the US strikes. According to the Jewish state, the nuclear fuel remained at the three sites when they were hit.

In the same article, the AP cited two unnamed officials from the US Defense Threat Reduction Agency (DTRA), who said they are still unaware if the GBU-57 Massive Ordnance Penetrator munitions were able to reach the depths they had been engineered for. The DTRA was involved for decades in designing the "bunker-buster" bombs specifically to target Iran's nuclear facilities.

Iranian President Masoud Pezeshkian told US journalist Tucker Carlson earlier this week that Tehran has so far been unable to access its nuclear sites after what he labeled "unlawful attacks" by the US. However, according to the president, it was already clear that "many of the pieces of equipment and the facilities there have been severely damaged."

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On Monday, Russian Foreign Minister Sergey Lavrov offered Moscow as a mediator between Tehran and Washington if the sides agree to resume nuclear talks, which had been halted following the US strikes. Russia previously condemned the US and Israeli attacks on Iran, warning that they significantly undermined the nuclear non-proliferation regime.