Setting levelset with vtu file

Hi, I would like to use a levelset function along with a metric field to remesh a domain. From an implementation standpoint it would be easier for me to give both of them to mmg, along with the mesh, in a vtu file. Unfortunately I am unable to use the levelset, even when I try to use it as the only pointdata with my mesh. I always get “Error: 1 UNEXPECTED DATA FIELD(S)” which indeed comes from the unrecognized levelset data field. Is there a way to do it this way or do I have to write .sol file ?