Allowing the appeal of the assessee the Tribunal held that, Assessing Officer issued notice under S.148 after four years from end of relevant assessment year without obtaining sanction under S. 151, was unjustified and consequently, entire reassessment proceedings stood vitiated.  Even if assessment was reopened in consequence of or to give effect to any finding or direction of Appellate Authority, requirement of sanction under section 151 is mandatory for issuing notice. ( AY. 2006 -07)