40. Notwithstanding anything to the contrary in sections 30 to 38, the following amounts shall not be deducted in computing the income chargeable under the head Profits and gains of business or profession,
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(ia) any interest, commission or brokerage, rent, royalty, fees for professional services or fees for technical services payable to a resident, or amounts payable to a contractor or sub-contractor, being resident, for carrying out any work (including supply of labour for carrying out any work), on which tax is deductible at source under Chapter XVII-B and such tax has not been deducted or, after deduction, has not been paid during the previous year, or in the subsequent year before the expiry of the time prescribed under sub-section (1) of section 200 :
Provided that where in respect of any such sum, tax has been deducted in any subsequent year or, has been deducted in the previous year but paid in any subsequent year after the expiry of the time prescribed under sub-section (1) of section 200, such sum shall be allowed as a deduction in computing the income of the previous year in which such tax has been paid
The aforesaid provision contained in section 40(ia) clearly states if the TDS had to be deducted on any payment which is an expense, such expense shall be allowed as business expense only in year in which tax is deducted and deposited .