The stamps issued by the General Post Office are classified as International stamps. Once the issuing stamp and the value thereof is recognized through reciprocity, the rest of the credentials of that particular Government follow.
In late May, 2015, upon mutual recognition of legal positions between The United States of America and the United States Postal Service (USPS), an agreement has been reached. Offer, acceptance, performance and consideration has been completed by and between the two international entities.
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