As per section 201(1A) of the Act, any person who is required to deduct the tax does not deduct the whole or any part of the tax or after deducting fails to pay the tax as required by or under this Act, he or it shall be liable to pay simple interest,at one per cent for every month or part of a month on the amount of such tax from the date on which such tax was deductible to the date on which such tax is deducted.
In the given case the liability to deduct TDS arises in the month of March since the threshold of 100,000 is exceeded in the same month and hence no interest liability for any previous months.