reiumbursment on supply of diesel

[yashpal madan]

We are providing Generator Set to banks on monthy rental basis.some banks are paying fix amount including supply of diesel,maintenence & operation of set and we charge GST @18% on fix amount.
Some banks are paying rent of generator @10000 p.m which include operation & maintenence plus diesel consumption @ 8 liter per hour at market diesel rates as per running of Generatror depending on power supply situation.
We generate two bills one for rent of generator and second for reimbursement of diesel.
On rent bill we charged 18%GST and we are not charging GST on reimbursement of diesel as petrolieum product are not in GST.
Please suggest me this is right or we should charge GST on reimbursement of diesel bill as bank are not ready to pay GST on diesel

AI Summary

Taxable value inclusion of reimbursements: diesel costs incurred to provide rental service must be part of the service value.
Diesel reimbursements paid to a supplier of rented generator sets are expenses incurred in providing a taxable service and must be included in the taxable value under valuation rules. Diesel being outside the tariff does not exclude it from value when it is an expense component of the supply. The pure agent exclusion applies only if strict conditions are met-contractual appointment, no title, recipient authorization, separate invoice disclosure, and that the procured supplies are additional-otherwise such reimbursements are includible.