What is the primary action taken if the requirements for a foreign phytosanitary certificate (PC) are not met or unknown?

The primary action taken when the requirements for a foreign phytosanitary certificate are not met or unknown is to refuse to certify. This action is essential to ensuring that phytosanitary measures are upheld to prevent the introduction and spread of plant pests and diseases. By refusing to certify, the USDA maintains strict compliance with phytosanitary standards, safeguarding domestic agriculture and natural resources.

When there is uncertainty about the requirements or when the documentation does not meet established guidelines, issuing a provisional certificate or requesting additional documentation might not provide the necessary assurance that the consignment is pest-free or compliant. Similarly, consulting with foreign authorities may delay the process without ensuring immediate compliance. Thus, the refusal to certify helps uphold the integrity and effectiveness of phytosanitary regulations, making it the correct approach in such situations.