(a) Funds appropriated for the Inter-American Highway shall be used to enable the United States to cooperate with the Governments of the American Republics situated in Central America—that is, with the Governments of the Republic of Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, and Panama—in the survey and construction of the Inter-American Highway within the borders of the aforesaid Republics, respectively. Not to exceed one-third of the appropriation authorized for each fiscal year may be expended without requiring the country or countries in which such funds may be expended to match any part thereof, if the Secretary of State shall find that the cost of constructing said highway in such country or countries will be beyond their reasonable capacity to bear. The remainder of such authorized appropriations shall be available for expenditure only when matched to the extent required by this section by the country in which such expenditure may be made. Expenditures from the funds available on a matching basis shall not be made for the survey and construction of any portion of said highway within the borders of any country named herein unless such country shall provide and make available for expenditure in conjunction therewith a sum equal to at least one-third of the expenditures that may be incurred by that Government and the United States on such portion of the highway. All expenditures by the United States under the provisions of this section for material, equipment, and supplies shall, whenever practicable, be made for products of the United States or of the country in which such survey or construction work is being carried on. Construction work to be performed under contract shall be advertised for a reasonable period by the Minister of Public Works, or other similar official, of the government concerned in each of the participating countries and contracts shall be awarded pursuant to such advertisements with the approval of the Secretary. No part of the appropriations authorized shall be available for obligation or expenditure for work on said highway in any cooperating country unless the government of said country shall have assented to the provisions of this section; shall have furnished satisfactory assurances that it has an organization adequately qualified to administer the functions required of such country under the provisions hereof; and then only as such country may submit requests, from time to time, for the construction of any portion of the highway to standards adequate to meet present and future traffic needs. No part of said appropriations shall be available for obligation or expenditure in any such country until the government of that country shall have entered into an agreement with the United States which shall provide, in part, that said country—

(1) will provide, without participation of funds authorized, all necessary rights-of-way for the construction of said highway, which rights-of-way shall be of a minimum width where practicable of one hundred meters in rural areas and fifty meters in municipalities and shall forever be held inviolate as a part of the highway for public use;

(2) will not impose any highway toll, or permit any such toll to be charged, for use by vehicles or persons of any portion of said highway constructed under the provisions of this section;

(3) will not levy or assess, directly or indirectly, any fee, tax, or other charge for the use of said highway by vehicles or persons from the United States that does not apply equally to vehicles or persons of such country;

(4) will continue to grant reciprocal recognition of vehicle registration and drivers’ licenses in accordance with the provisions of the Convention for the Regulation of Inter-American Automotive Traffic, which was opened for signature at the Pan American Union in Washington on December 15, 1943, and to which such country and the United States are parties, or of any other treaty or international convention establishing similar reciprocal recognition; and

(5) will provide for the maintenance of said highway after its completion in condition adequately to serve the needs of present and future traffic.

(b) The survey and construction work authorized by this section shall be under the administration of the Secretary, who shall consult with the appropriate officials of the Department of State with respect to matters involving the foreign relations of this Government, and such negotiations with the Governments of the American Republics named in subsection (a) of this section as may be required to carry out the purposes of this section shall be conducted through, or as authorized by, the Department of State.

(c) The provisions of this section shall not create nor authorize the creation of any obligations on the part of the Government of the United States with respect to any expenditures of highway construction or survey heretofore or hereafter undertaken in any of the countries enumerated in subsection (a) of this section, other than the expenditures authorized by the provisions of this section.

(d) Appropriations made pursuant to any authorizations heretofore, or hereafter enacted for the Inter-American Highway shall be considered available for expenditure by the Secretary for necessary administrative and engineering expenses in connection with the Inter-American Highway program.