We describe the type IIB supergravity background on AdS(3) x S-3 x T-4 usin
g the potentials of AdS(3\4) x S-3 x T-4 and we use the supersolvable algeb
ra associated to AdS(3\4) to compute the k gauge fixed type IIB string acti
on. From the explicit form of the action we can clearly see how passing fro
m pure NSNS backgrounds to pure RR backgrounds the WZW term disappears.