Letter of credence
A letter of credence (French: Lettre de créance) is a formal diplomatic letter that designates a diplomat as ambassador to another sovereign state. Commonly known as diplomatic credentials, the letter is addressed from one head of state to another, asking them to give credence (French: créance) to the ambassador's claim of speaking for their country. The letter is presented personally by the ambassador-designate to the receiving head of state in a formal ceremony, marking the beginning of the ambassadorship.
Letters of credence are traditionally written in French, the lingua franca of diplomacy.[1] However, they may also be written in the official language of the sending state.[2][3]
Language of letters[edit]
Letters of credence between two monarchs of equal rank will typically begin with the salutation "Sir My Brother" (or "Madame My Sister", in the case of a female monarch) and close with the valediction "Your Good Brother" (or Sister, in the case of a female monarch).