Prior approval for industrial training from icai

What is the complete procedure for Industrial Training Practically? Do i require to take any Prior Approval From ICAI for Industrial Training ? or Simply Submitting of Form 104 is Enough.

AS per regulation 51 of ICAI I have intimated my principle before 3 month of completion of second year CA Articleship, and duly submitted for 109 to ICAI. 

But now i have received a letter from ICAI & it says that, i do have to send a request on plain paper giving the reason for Termination / Transfer along with photocopy of proof duly recommended by my employer. Please suggest me as what should I do.

 Looking for the response at the very Earliest

Thanks in Advance