  A standard bicovariant differential calculus on a quantum matrix space ${\tt
Mat}(m,n)_q$ is considered. The principal result of this work is in observing
that the $U_q\frak{s}(\frak{gl}_m\times \frak{gl}_n))_q$ is in fact a
$U_q\frak{sl}(m+n)$-module differential algebra.
