The invention relates to a humanized monoclonal antibody or fragment thereofwhich specifically binds to human interleukin-2 (IL2), wherein said humanizedmonoclonal antibody neutralizes the activity of human IL2 by binding to saidhuman IL2 prior to, during, and/or subsequent to the binding of said human IL2to the human IL2-receptor, and wherein the light chain variable region of saidhumanized monoclonal antibody comprises in its second framework region thecontiguous amino acid sequence KAPKA at amino acid positions 42-46.