tds to be deducted or not

hiiiiiiiiii all

i have a doubt on TDS that tds to be deducted or not in the following case.

MR A a seller has the termed & condition that if some one make late payment he will charge intrest @ 15 % on the amount, & our client has make him a late payment which has attract  the intrest payment of RS. 15 lakh,

so my question is that wether he should deducted the TDS on intrest or not.

if yes under which section of IT act