(1) Notwithstanding subsection (5) of section 396 or subsection (3) of section 397, in ascertaining for the purposes of those sections whether and to what extent a company has incurred a loss in carrying on a trade in the State through a branch or agency, the interest on, and other profits or gains from, a security held by or for the branch or agency shall be treated as a trading receipt of the trade if such interest or other profits or gains would, if sections 43, 49 and 50 had not been enacted, have been so treated, or have been included in an amount so treated.
(2) Subsection (1) shall apply for the purposes of ascertaining whether and to what extent a company has incurred a loss where apart from that subsection the company would be treated as having incurred a loss and that loss would be -
(a) set-off against the trading income or profits (whether of that company or any other company) of, or
(b) incurred in,
an accounting period.