GST liability, including interest on delayed payment, must be...

GST liability, including interest on delayed payment, must be determined strictly under the statute, and interest arises by operation of law where the fiscal enactment so provides. In the absence of statutory power, authorities cannot waive or reduce interest, or permit filing or amendment of returns in a manner not contemplated by the GST scheme; blanket directions on penalty and limitation are likewise unsustainable. The note also distinguishes contractual reimbursement of incremental GST from statutory tax liability: any claim for reimbursement is an inter se matter between contracting parties and cannot alter the GST regime or bind tax authorities.