Members of the public watching the Coronation on television, online or gathered in the open air at big screens will be asked to pledge their allegiance to King Charles in a "chorus of millions of voices" on Saturday.
Charles' ceremony will include the first Homage of the People - a modern addition that will see people across the UK and overseas realms invited to swear an oath to the new monarch.
Lambeth Palace said it was hoped the significant change to the historic service will result in a "great cry around the nation and around the world of support for the King".
