I am interested when I become liable (responsible) for loan repayment through the US Bank. From the time the Loan was approved or from the time I start attending the MBA program

I am an international student and thus loan approval is necessary for receiving my visa documents (such as I-20). Let's say I sent a request for an MBA loan and the loan was approved by the lender. I will then go with my visa documents (sent by the Business school?s international office) to the US embassy in my home country. But, my visa application is being rejected by the US embassy. So, I end up not coming to study in the MBA program. Will I be responsible for re-payment of the loan in the above situation? Thanks

Let me understand: If your visa application is rejected, and you don't do your MBA, you will not TAKE the loan in the first place (even if it has been approved), because, what would you need the money for?
Thus, if you don't take you loan you won't need to re-pay anything either.

Or did you mean something else?