Section 18(a) in The Integrated Goods and Services Tax Act, 2017
(a)central tax in accordance with the provisions of sub-section (5) of section 49 of the Central Goods and Services Tax Act, the amount collected as integrated tax shall stand reduced by an amount equal to the credit so utilised and the Central Government shall transfer an amount equal to the amount so reduced from the integrated tax account to the central tax account in such manner and within such time as may be prescribed;
