The multipolarity of a soft (E gamma = 3.3(1) MeV) resonance in the total radiative strength function (RSF) of Yb-172 is determined. For this reason, the level density and total RSF of Yb-172 have been extracted from primary-gamma spectra from the Yb-173(He-3,alpha gamma)Yb-172 reaction. In a second experiment, two-step-cascade (TSC) intensities have been measured in the Yb-171(n(th), gamma gamma)Yb-172 reaction. These intensities are compared to statistical-model calculations which are entirely based on experimental values of the level density and RSF from the former experiment. This comparison implies M1 assignment of the soft resonance. The strength of the M1 resonance is B(M1 up arrow) = 6.5(15) mu(N)(2). (c) 2005 Elsevier B.V. All rights reserved.