Zamolodchikov operator-valued relations for SL(2,R)_k WZNW model

An infinite set of operator-valued relations that hold for reducible representations of the sl(2)_k algebra is derived. These relations are analogous to those recently obtained by Zamolodchikov which involve logarithmic fields associated to the Virasoro degenerate representations in Liouville theory. The fusion rules of the sl(2)_k algebra turn out to be a crucial step in the analysis. The possible relevance of these relations for the boundary theory in the AdS_3/CFT_2 correspondence is suggested.