Русско-англо-русский юридический словарь

A marriage certificate is an official statement that two people are married. In most jurisdictions, a marriage certificate is issued by a government official only after the civil registration of the marriage. (Wikipedia)

decree – an official statement that something must happen, made by a leader, government, etc.: The Dutch government issued a decree laying down strict rules on the age of veal calves and how they should be housed. (Cambridge Academic Content Dictionary)

In an official statement, she formally announced her resignation (Longman Dictionary of Contemporary English)