Section 135National Internal Revenue Code of 1997 (Republic Act No. 8424), Sec. 135

Petroleum Products Sold to International Carriers and Exempt Entities or Agencies. - Petroleum products sold to the following are exempt from excise tax:

(a) International carriers of Philippine or foreign registry on their use or consumption outside the Philippines: Provided, That the petroleum products sold to these international carriers shall be stored in a bonded storage tank and may be disposed of only in accordance with the rules and regulations to be prescribed by the Secretary of Finance, upon recommendation of the Commissioner;

(b) Exempt entities or agencies covered by tax treaties, conventions and other international agreements for their use of consumption: Provided, however, That the country of said foreign international carrier or exempt entities or agencies exempts from similar taxes petroleum products sold to Philippine carriers, entities or agencies; and

(c) Entities which are by law exempt from direct and indirect taxes.