Official phone calls!! :/

Official phone calls!! :/ Hello reddit, So I got allocated to this project (IT) which requires to (*sigh) call the customer and update her about the current progress. It is like nightmare becoming true for me, firstly I never initiate any phone calls to anyone and secondly English in not the first language for me. The wait is killing me, as i'm the fresher! I don't want anyone to know that I stutter. Please help me, what to do..