Section 12 of the Principal Act is hereby amended in paragraph (a) of subsection (1) by the insertion of the following subparagraphs after subparagraph (iiib):
"(iiic) the tax chargeable during the period, being tax for which he is liable by virtue of section 4(8), in respect of a supply of immovable goods deemed to be supplied by him:
Provided that this subparagraph shall apply only where he would be entitled to a deduction of that tax elsewhere under this subsection if the goods in question were supplied to him by another person and if he had not been deemed to have supplied them in accordance with section 4(8),
(iiid) the tax chargeable to him during the period by other taxable persons in respect of goods or services directly related to a supply of immovable goods which is deemed not to be supplied by him in accordance with section 4(8),".