Caramac and Animal Bar are to be discontinued by Nestle after more than 60 years.
The former, a gold-coloured confectionary, first hit the shelves in the UK in 1959 after being rolled out by its original creator, Mackintosh's.
Four years later, in 1963, the Animal Bar - a milk chocolate bar which has two different named animals moulded on the surface - launched.
However, sales of both have "steadily declined" over the past few years, according to Nestle, which bought the brand as part of a takeover in 1998.
The company has now decided to pull the products altogether.
"We are very sorry to disappoint fans of Caramac," Nestle said in a statement.
"There has been a steady decline in its sales over the past few years and unfortunately we had to make the difficult decision to discontinue it.
"We know fans will be disappointed to see it go, but this change will enable us to focus on our best-performing brands, as well as develop exciting new innovations to delight consumers' tastebuds."
In an update, the company told Sky News Animal Bar is also being discontinued "due to the low performance of the product and a steady decline in its sales over the past few years".
Caramac bars - named from an abbreviation of caramel and Mackintosh's - are made from condensed milk, butter, various flavourings and sugar.
Despite often sharing the shelves with chocolate bars, they do not contain any cocoa.
Nestle paired Caramac with its popular Kit Kat snack in 2005 to make a limited edition Caramac Kit Kat bar.
The collaboration was such a success, it was brought back by popular demand in 2007.
Nestle also rolled out Caramac buttons in 2015.
(c) Sky News 2023: Caramac and Animal Bar to be discontinued after more than 60 years
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