  Vector meson ($V = \omega, \phi$) production in near-threshold elementary
nucleon-nucleon collisions $pp\to ppV$, $pn\to pnV$ and $pn\to dV$ is studied
within an effective meson-nucleon theory. It is shown that a set of effective
parameters can be established to describe fairly well the available
experimental data of angular distributions and the energy dependence of the
total cross sections without explicit implementation of the Okubo-Zweig-Iisuka
rule violation. Isospin effects are considered in detail and compared with
experimental data whenever available.
