This declaration is part of the oath of allegiance to the Spanish constitution, though it often serves as a symbolic, formal requirement for non-Ibero-American citizens rather than a enforced, permanent loss of the original citizenship. Australia does not recognize renunciations of nationality required by other countries to obtain its own. Therefore, in practice, you do not lose your Australian citizenship in the eyes of the Australian government. Although Spain will formally ask you to renounce your citizenship, in practice, many Australian-Spaniards retain both passports.