European and American officials quoted saying Biden administration wants Iran to roll back activities to 2015 level, but Tehran doesn't want to give up advanced centrifuges

Fire injures at least 2; incident comes amid escalating tensions with Israel, which Tehran has blamed for an earlier blast at Natanz nuclear plant

Incident follows a series of events attributed to a shadow war between Iran and Israel, including attacks on regional shipping and sabotage at Iran's Natanz nuclear facility

Mossad chief, national security adviser head to DC Monday to lobby against US return to nuke deal; IDF chief backs out and delegation delays trip due to security flare-up

Top Iranian atomic official and parliament speaker announce development, five days after Natanz attack -- blamed on Israel -- reportedly destroys thousands of centrifuges

UN agency confirms Natanz facility will begin increasing operations shortly, days after sabotage said to have damaged thousands of centrifuges

As negotiations thrown into disarray following Natanz facility sabotage, supreme leader Khamenei warns the US time could be running out

Tehran demands all sanctions since 2017 under Trump administration be lifted; Washington says it offered 'very serious' ideas but questions Iran's intentions.

Washington says it offered 'very serious' ideas to Tehran on rescuing deal, and is waiting for its efforts to be 'reciprocated'

Delegates in Vienna pledge to continue negotiations, as Tehran reiterates demand that US drop all sanctions before returning to compliance with nuclear deal