Article 607. National Security Measures
Subject to Annex 607 (TLCAN: Anexo 607), no Party may adopt or maintain a measure restricting imports of an energy or basic petrochemical good from, or exports of an energy or basic petrochemical good to, another Party under Article XXI of the GATT or under Article 2102 (TLCAN: Art. 2102) (National Security), except to the extent necessary to:
Supply a military establishment of a Party or enable fulfillment of a critical defense contract of a Party;
Respond to a situation of armed conflict involving the Party taking the measure;
Implement national policies or international agreements relating to the non-proliferation of nuclear weapons or other nuclear explosive devices; or
Respond to direct threats of disruption in the supply of nuclear materials for defense purposes.