Section 1 of Executive Order 459 provides that negotiations on such contracts or agreements may only take place with the participation of the Ministry of Foreign Affairs and with the appointment of the head of the Philippine negotiating body, in coordination with the Ministry. It is time for our foreign affairs experts to speak out on this matter of national interest. His political loyalty is believed to have caused Senator Tolentino to forget his international law, which was his main subject as a doctoral student at the University of London. Or maybe he just forgot. In Magallona, where we question the constitutionality of the new basis law, Republic Act 9522, Judge Carpio had stated that there was no conflict between the provisions of the law of the sea on maritime claims and the provisions of the national territory of the 1987 Constitution. But this would not be an executive agreement, but a sad way of negotiating our national heritage for absolutely nothing, a full-fledged treaty is only necessary if an agreement involves changes in Philippine national policy and therefore the agreement must be submitted to the Senate for ratification. On the other hand, if an agreement only implements existing contractual obligations, laws or guidelines, an executive agreement will suffice.-Paolo Miguel Q. Bernardo, contributor A treaty needs the approval of the Senate to be valid, while an executive agreement only requires the signature of the president or his representative, without the approval of the Senate. . . .