PETA was recently told by a whistleblower of alleged animal welfare issues during filming of The Hobbit trilogy, including claims that as many as 27 animals had died during production.
Jackson and his co-producers strongly denied the allegations in a statement released on Monday (November 19), saying: "Any incidents that occurred that were brought to [producers'] attention as regards to [animal] care were immediately investigated and appropriate action taken."
PETA has now said in a statement obtained by The Wrap: "[Peter] Jackson should be giving a firm assurance that this will never happen again.
"He is the CGI master, and has the ability to make the animals and other interesting creatures in his movies 100% CGI, and PETA calls on him again to do so."
New Line Cinema and Warner Bros have also stood by Jackson, saying in their own joint statement that they refute and condemn allegations of animal abuse on The Hobbit movies.
The studios have also alleged that the claims were made by "freelance animal wranglers" who were dismissed from the production.
The first instalment in The Hobbit trilogy - titled The Hobbit: An Unexpected Journey - is due to be released on December 14.
Photo gallery - 'The Hobbit' character posters: