Nestle says "forced labour has no place in our supply chain" following a U.S. class action lawsuit that alleges the Swiss food company knowingly supported a system of slave labour and human trafficking to make its Fancy Feast cat food.

Nestle didn't deny the allegations in an email Sunday to The Associated Press but said its guidelines require suppliers to respect human rights. It outlined steps Nestle has taken to rid forced labour from its seafood supply chain.

The Hagens Berman law firm filed the suit Thursday on behalf of pet food purchasers. It said they wouldn't have bought the seafood-based pet food if they had known "slave labour" was used to obtain some ingredients in the products imported by Nestle and partner Thai Union Frozen Products.