  Using the Anderson model in the Kondo regime, we calculate the persistent
current j in a ring with an embedded quantum dot (QD) as a function of the
Aharonov-Bohm flux Phi for different ring length L, temperature T and
broadening of the conduction states delta . For T=delta =0 and L >> xi, where
xi is the Kondo screening length, Lj tends to the value for a non interacting
ideal ring, while it is suppressed for a side coupled QD. For any L/xi, Lj is
also suppressed when either T or delta increase above a fraction of the level
spacing which depends on Phi.
