DUBAI, United Arab Emirates (AP) — Iran’s nuclear program has been targeted by diplomatic efforts and sabotage attacks over the last decade, with the latest incident striking its underground Natanz facility. The attack Sunday at Natanz comes as world powers try to negotiate a return by Iran and the U.S. to Tehran’s atomic accord. The sabotage threatens to upend those negotiations and further heighten regional tensions across the Mideast. It comes at a sensitive time for outgoing President Hassan Rouhani. He is term-limited from serving again. If Iran can’t regain the benefits of the deal, it could boost hard-liners within the Islamic Republic ahead of June’s presidential election.