Two forestry companies colluded for more than a decade to control the prices of toilet paper and other products, according to Chile's competitive practices regulator.

Economy Minister Luis Felipe Cespedes said on Thursday that the collusion between the market's biggest players was outrageous and affected the poorest Chileans the most.

Chilean President Michelle Bachelet called the alleged collusion by companies that control 90 percent of the toilet-paper market "extremely serious".