2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/150699An application of the Newman-Penrose dyad formalism for description of tensionless (null) string dynamics in 4D Minkowski spacetime is studied in a background of antisymmetric fields. We present a special class of background antisymmetric fields which admits exact solutions of the null string motion equations and formulate a sufficient condition of the absence of interaction of a null string with such fields.8 pages, LaTeX, submitted to Classical and Quantum GravityHigh Energy Physics - Theorytext