President Hassan Rouhanis message is as follows:

In the Name of Allah, the Most Beneficent, the Most Merciful

Dear Mr Vladimir Vladimirovich Putin,

President of the Russian Federation,

The crash of Russias Saratov flight Antonov An-148 caused great grief and sorrow. 
Expressing condolences and sympathy to your Excellency and the families of the victims of the plane crash, I wish your Excellency health and success and the people of the Russian Federation prosperity and felicity.

Hassan Rouhani