Top EU diplomat Josep Borrell on Monday held talks in the Iranian capital on a mission aimed at lowering tensions over the Islamic republic’s nuclear programme. Borrell’s trip, his first to Iran since taking office, follows a spike in tensions between arch foes Washington and Tehran following the January 3 assassination in Baghdad of a top Iranian general in a US drone strike. The 2015 nuclear deal between Tehran and a group of world powers has been crumbling since US President Donald Trump withdrew from it in 2018, and Washington has since stepped up sanctions and a campaign of “maximum pressure” against Iran.