11.—(1) The interest of an undertaking in an associated undertaking, and the amount of profit or loss attributable to such an interest, shall be shown—
(a)by the equity method of accounting, or
(b)if the generally accepted accounting principles under which the accounts have been prepared allow it to be accounted for by another method, by that method.
(2) If an interest is accounted for in accordance with sub-paragraph (1)(b), the method used must be disclosed in the notes to the accounts.
(3) Where the associated undertaking is itself a parent undertaking, the net assets and profits or losses to be taken into account are those of the parent and its subsidiary undertakings (after making any consolidation adjustments).