Interest earned on NRE or Non Resident External Fixed Deposit Account is tax free provided you maintain your NRI status.
So,as and and when you return back to India and become a Resident Indian, you will need to offer your interest income to tax and show the same in your Income tax return.
So,the moment you return to India and re-designate your accounts in compliance with FEMA (Foreign Exchange Management Act), you need to offer your interest income to tax.
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