Who should be responsible for petty cash in a large company?

Petty cash officer / Cashier / Petty cash custodian

Prime responsibility for  petty cash rests with the cashier or the person entrusted with the responsibility of handling the pettyy cash.In case of misdeeds and mistakes, the additional  responsibility of checking will fall on the superior for negligence.

It depends on the complexity of organisation. If it has multiple offices and plants etc, then accountant and operational managers can be responsible for handling petty cash imprest system.

surely, an accountant...