Cadbury says it is "disappointed" after losing its royal warrant after 170 years.
The chocolate maker behind festive favourites such as Heroes and Dairy Milk is among the brands that have had their warrants withdrawn under King Charles.
The development was reported in a list published by Buckingham Palace's Royal Warrant Holders Association.
Warrants are granted as a special mark of recognition to people or companies who have regularly supplied goods or services to the royal household.
Cadbury was first granted the warrant in 1854.
Unilever, which owns consumer brands Dove and Lipton, was also stripped of its warrant.
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It comes after the King was urged by campaign group B4Ukraine to take warrants from companies "still operating in Russia" after the invasion of Ukraine.
B4Ukraine named Mondelez, which owns Cadbury, and Unilever, in its campaign.
However, Bacardi and Samsung were also named in the B4Ukraine list and have not been stripped of their royal warrants, indicating the decision is not linked to Russia's invasion.
A Mondelez International spokesperson said: "Whilst we are disappointed to be one of hundreds of other businesses and brands in the UK to not have a new warrant awarded, we are proud to have previously held one, and we fully respect the decision."
A Unilever spokesperson said: "We are very proud of the long history our brands have supplying the royal household and of the warrants they have been awarded during this time, most recently by Her Majesty Queen Elizabeth II.
"The granting of royal warrants is a matter for the royal household."
(c) Sky News 2024: Cadbury 'disappointed' after losing royal warrant it has held since 1854
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