First of all depending on the type of IRA you may not have to pay taxes on withdrawals in the US at all. If you are withdrawing your principle from a Roth IRA then you don't owe taxes. Only when you withdraw the gains do you pay taxes on it.
You have two options for withdrawals:
Lump Sum Withdrawal: If you take a lump sum withdrawal you will owe taxes to the US (30% for non-resident aliens of the US), and according to DTAA; Article 23, you will file your taxes with India declaring your IRA or 401(k) withdrawal proceeds and claim credit on the taxes you paid to the US.
Monthly Pension Withdrawal: You can also receive monthly pension payments and you will only be taxed in the country in which you are a resident of. This is according to DTAA, Article 20. You would then have to submit necessary documentation to your payer in the US so that they do not withhold any taxes in the US.
Just as a side note it might be just better to keep the money where it is and let it grow or roll it over to a Roth IRA if you are currently in a lower tax bracket for maximum savings of your principle.
Here is a link with more detailed information of what I provided you: http://articles.economictimes.indiatimes.com/2012-01-25/news/30663129_1_taxable-income-nri-401k-plan