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.

WK Kellogg, the maker of iconic American cereal brands, will be folded into the privately held owner of Nutella and Tic Tacs in a $3.1 billion deal.

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,