Where a registered dealer purchases goods from a dealer in West Bengal who has applied for registration within thirty days of his incurring liability to pay tax under sub-section (2) of section 23 and who has issued a tax invoice, such dealer, subject to the satisfaction of the appropriate authority under the Act, may, for the purpose of determination of his turnover of purchases, deduct under clause (d) of sub-section (2) of section 17, from his turnover of purchases such amount of purchase, and he shall, on demand by the appropriate authority under the Act, furnish the relevant tax invoice and such other documents evidencing such purchase:

Provided that where the application for registration of the dealer has been rejected, no deduction shall be allowed on such purchases from the date of order of rejection of the application.