The third amending of the Treaty occurred at a special general conference in August 1992, when amendments to Articles 14-16 and 19 were adopted. The most significant of these was a change in Article 16 designating the IAEA as having the sole authority to conduct special inspections of Tlatelolco parties; the original text gave this authority both to the IAEA and to OPANAL, the Treaty's executive agency.

The complete text of this third set of the amendments is reproduced below:

Article 14

2. The Contracting Parties shall simultaneously transmit to the Agency a copy of the reports sent to the International Atomic Energy Agency in relation to matters subject to the present Treaty which are relevant to the Agency's work.

3. The information provided by the Contracting Parties cannot be divulged or communicated to third parties, totally or partially, by the recipients of the reports except with the express consent of the former.

Article 15

1. At the request of any of the Parties, and with the authorization of the Council, the Secretary General may request any of the Contracting Parties to provide the Agency with complementary or supplementary information regarding any extraordinary fact or circumstance which affects compliance with the present Treaty, explaining the reasons he/they had for such action. The Contracting Parties commit themselves to cooperate quickly and fully with the Secretary General.

2. The Secretary General will immediately inform the Council and the Contracting Parties about such requests and their respective replies.

Article 16

1. The International Atomic Energy Agency has the power of carrying out special inspections in conformity with Article 12 and with the agreements referred to in Article 13 of this Treaty.

2. At the request of any of the Contracting Parties, and following the procedures established under Article 15 of the present Treaty, the Council may submit to the consideration of the International Atomic Energy Agency a requisition that the latter initiate the arrangements required for the carrying out of a special inspection.

3. The Secretary General shall request the General Director of the International Atomic Energy Agency to transmit to him in a timely manner the information sent by the former to the IAEA Board of Governors regarding the conclusion of the said special inspection. The Secretary General shall promptly impart such information to the Council.

4. By the Agency or the Secretary General, the Council shall transmit such information to all of the Contracting Parties.

Article 19

The Agency may conclude agreements with the International Atomic Energy Agency as are authorized by the General Conference and as it considers appropriate to facilitate the efficient operation of the Control System established by this Treaty.

Article 20

1. The Agency may also enter into relations with any international organization or body, especially any which may be established in the future to supervise disarmament or measures for the control of armaments in any party of the world.

2. The Contracting Parties may, when they see fit, request the advice of the Inter-American Nuclear Energy Commission on all technical matters connected with the application of this Treaty with which the Commission is competent to deal under its Statute.