Ferrero Group is buying WK Kellogg Co. for roughly $3 billion. The deal will see the parent company of several candy bar and snack brands add a collection of well-known breakfast cereals to its holdings,

Ferrero, the European confectionery giant behind Nutella and Ferrero Rocher, is set to acquire WK Kellogg Co ., the maker of Froot Loops and other classic American cereals, in a $3.1 billion deal, according to a press release issued Thursday.

The Italian candy maker behind Ferrero Rocher and Nutella is nearing a roughly $3 billion deal to buy the breakfast-cereal conglomerate WK Kellogg, according to people familiar with the matter. Ferrero,