The President can declare an emergency for any occasion or instance when the President determines federal assistance is needed. FEMA Emergency declaration supplements State and local or Indian tribal government efforts in providing emergency services, such as the protection of lives, property, public health, and safety, or to lessen or avert the threat of a catastrophe in any part of the United States.
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When an emergency exists for which the primary responsibility rests with the Federal government, the President may declare an emergency without a request from the Governor of the affected State or the Tribal Chief Executive of the affected Tribe. Such an emergency declaration does not prevent the Governor or Tribal Chief Executive from subsequently requesting a major disaster declaration for other unmet needs caused by the event.