Identical question of law pending before Supreme Court: revenue may defer immediate appeal and seek tribunal leave pending final decision. Section 158AA permits the Commissioner or Principal Commissioner, during its operative period, to direct the Assessing Officer to apply to the Appellate Tribunal for permission to file an appeal on an identical question of law pending before the Supreme Court, provided the assessee accepts identity; absent acceptance the Commissioner must proceed under section 253(2) or (2A). If the Commissioner (Appeals) order conflicts with the Supreme Court's final decision, the Commissioner may direct an appeal to the Appellate Tribunal, to be filed within 60 days of communication of the Supreme Court order.