WASHINGTON — Israel has concluded that some of Iran’s underground stockpile of near-bomb-grade enriched uranium survived American and Israeli attacks last month and may be accessible to Iranian nuclear engineers, according to a senior Israeli official.

The senior official also said that Israel had begun moving toward military action against Iran late last year after seeing what the official described as a race to build a bomb as part of a secret Iranian project.

The official, who spoke on the condition of anonymity, said Israeli intelligence picked up the nuclear weapons activity soon after the Israeli air force killed Hassan Nasrallah, the longtime leader of Hezbollah, the Iran-backed militia in Lebanon. That observation prompted Israeli Prime Minister Benjamin Netanyahu to prepare for an attack.

In the days surrounding Israel’s attack on Iran in mid-June and President Donald Trump’s subsequent decision to join in the action, U.S. intelligence officials said they had seen no evidence of a move by Iran to weaponize its stockpile of near-bomb-grade uranium.

— The New York Times