(a) In-quota lamb meat may only be entered as a product of a participating country if the United States importer makes a declaration to the United States Customs Service, in the form and manner determined by the United States Customs Service, that a valid export certificate is in effect with respect to that lamb meat product.

(b) To be valid, an export certificate shall:

(1) Be issued by or under the supervision of the government of the participating country;

(2) Specify the name of the exporter, the product description and quantity, and the quota year for which the export certificate is in effect;

(3) Be distinct and uniquely identifiable; and

(4) Be used for the quota year for which it is in effect.