SECTION 1. Subparagraph (d) of the first paragraph of Section nine of Commonwealth Act Numbered Six hundred thirteen, otherwise known as the Philippine Immigration Act of 1940, as amended, is hereby further amended so as to read as follows:
“(d) An alien entitled to enter the Philippines under and in pursuance of the provisions of a treaty of commerce and navigation (1) solely to carry on substantial trade principally between the Philippines and the foreign state of which he is a national or (2) solely to develop and direct the operations of an enterprise in which, in accordance with the Constitution and the laws of the Philippines he has invested or of an enterprise in which he is actively in the process of investing, a substantial amount of capital; and his wife, and his unmarried children under twenty-one years of age, if accompanying or following to join him, subject to the condition that citizens of the Philippines are accorded like privileges in the foreign state of which such alien is a national."