Passport is just a travel document!!!
As I know and per the opinions in these forums, I believe that passport is just a travel document(also, proof of your citizenship in some countries). And hence, not a must at the time of interview for citizenship.
Anyway, that will be taken away at the time of citizenship(in case of Indian citizens as there is no dual citizenship policy).
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I am not an attorney or legal expert. The above is only my opinion.