UPDATE 2-US must return to interim deal, no ceasefire extension talks, senior Iranian source says

(Adds background and context throughout) * No talks have occurred on extending 60-day ceasefire, senior Iranian source says * Iran says Washington must return to June interim pact and set timetable

(The article has been published through a syndicated feed. Except for the headline, the content has been published verbatim. Liability lies with original publisher.)