US intelligence assessments indicate that strikes on Iranian nuclear sites set the country's atomic program back by up to two years, the Pentagon said on Wednesday.
"We have degraded their program by one to two years at least -- intel assessments inside the (Defense) Department assess that," Pentagon spokesman Sean Parnell told journalists, later adding: "We're thinking probably closer to two years."
American B-2 bombers hit two Iranian nuclear sites with massive GBU-57 bunker-buster bombs last month, while a guided missile submarine struck a third site with Tomahawk cruise missiles.
Israel launched an unprecedented air campaign targeting Iranian nuclear sites, scientists and top military brass on June 13 in a bid to end the country's nuclear program, which Tehran says is for civilian purposes but Washington and other powers insist is aimed at acquiring atomic weapons.
US President Donald Trump had spent weeks pursuing a diplomatic path to replace the nuclear deal with Tehran that he tore up during his first term in 2018, but he ultimately decided to take military action.
The US operation was massive, involving more than 125 US aircraft including stealth bombers, fighters and aerial refueling tankers as well as a guided missile submarine.
IAEA cooperation
Iran's suspension of cooperation with the UN nuclear watchdog, the International Atomic Energy Agency (IAEA), is unacceptable, US State Department spokeswoman Tammy Bruce said Wednesday.
Tehran officially suspended its cooperation with the IAEA, a move triggered by the unprecedented Israeli and US strikes on its nuclear facilities over 12 days in June.
"We'll use the word unacceptable, that Iran chose to suspend cooperation with the IAEA at a time when it has a window of opportunity to reverse course and choose a path of peace and prosperity," Bruce told a briefing in Washington.
Washington backed Israel's effort to damage Iran's nuclear program by bombing three nuclear sites overnight on June 21-22. Trump has since warned he will order more air strikes if Tehran tries to obtain nuclear weapons.
The Islamic republic has always denied it was seeking to develop an atomic weapon.
Bruce said Iran must cooperate without delay with the IAEA, including by providing "information required to clarify and resolve long-standing questions regarding undeclared nuclear material in Iran, as well as provide unrestricted access to its newly announced enrichment facility."
"Iran cannot and will not have a nuclear weapon," she repeated.