ReutersThe US has said it is not involved in Israel's bombardment of Iranian nuclear sites, an escalation that is threatening to send the region deeper into conflict. Secretary of State Marco Rubio released a statement soon after the strikes began, saying Israel had taken "unilateral action" and warning Iran against retaliation against the US."We are not involved in strikes against Iran and our top priority is protecting American forces in the region," Rubio said. "Let me be clear: Iran should not target U.S. interests or personnel."Earlier on Thursday, President Donald Trump had warned that a military operation against Iran would "blow" the negotiations his administration has been holding with Iran in a bid to curb its nuclear programme. The Israeli strikes - dubbed Operation Rising Lion - targeted Iran's nuclear programme and other military sites, according to a statement by the Israel Defence Force. Israeli Prime Minister Benjamin Netanyahu said the attack was necessary due to Iran's continued movement to "weaponise" enriched uranium and was critical to "Israel's very survival". Israel has declared a state of emergency and said the country expects retaliation. Netanyahu said the strikes against Iran would "continue for as many days as it takes". LIVE: Israel says it has launched strikes on Iran's nuclear sites as blasts heard across countryGlobal watchdog finds Iran failing to meet nuclear obligationsRubio's statement said Israel had advised the US that they believed this action was necessary for its self defence. "President Trump and the administration have taken all necessary steps to protect our forces and remain in close contact with our regional partners."Worried that an attack by Israel could provoke Iran to retaliate by targeting US military installations nearby, the US had already partially evacuated US embassy staff from Iraq. The state department had also limited the movement of its employees within Israel to the Tel Aviv area, as well, according to a social media post on Thursday. Trump has for some time been working to negotiate with Iran over limiting its nuclear programme, but a deal has so far been out of reach. "As long as I think there will be an agreement, I don't want them going in," Trump said of an Israeli strike earlier on Thursday, adding he would "love to avoid a conflict".The president's Middle East envoy Steve Witkoff was due to hold another round of talks with Iranian officials on Sunday.