Rule 128(9) prescribing the filing of Form No. 67 by the due date of the return, is directory and procedural. Non-compliance with this procedural requirement does not extinguish the substantive right to claim FTC. The provisions of DTAA override domestic law if they are more beneficial to the assessee and procedural compliance should not override the DTAAs substantive provisions, which guarantee relief from double taxation. Accordingly, AO was directed to allow FTC as per DTAA between India and Netherlands. (AY.  2020-21)