Simplify the following text for a Grade 15 native English-speaking person.
Original: Iranian president Mahmoud Ahmadinejad 's controversial comments , which included questioning the dimension of the Holocaust , have sparked discussions concerning Freiburg 's partnership with Isfahan .
Simplified: Iranian president Mahmoud Ahmadinejad 's , controversial comments , which included questioning the size of the Holocaust , have sparked questions about Freiburg 's partnership with Isfahan .