Iran nuclear talks to enter third day after 'progress' --- US Secretary of State John Kerry said important issues remained "unresolved". -- Talks between Iran and world powers on Tehran's nuclear programme are to enter an unscheduled third day in Geneva. -- Under a deal being floated, Iran could freeze expansion of its nuclear activity for limited sanctions relief. -- "There is more work to do," the US official told reporters after talks ended late on Friday evening. -- More BBC