We have searched for neutrinoless $tau$ lepton decays into $ell$ and $V^0$, where $ell$ stands for an electron or muon, and $V^0$ for a vector meson ($phi$, $omega$, $K^{*0}$, $bar{K}^{*0}$ or $rho^0$), using 543 fb$^{-1}$ of data collected with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. No excess of signal events over the expected background has been observed, and we set upper limits on the branching fractions in the range $(5.9-18) times 10^{-8}$ at the 90% confidence level. These upper limits include the first results for the $ell omega$ mode as well as new limits that are significantly more restrictive than our previous results for the $ell phi$, $ell K^{*0}$, $ell bar{K}^{*0}$ and $ell rho^0$ modes.
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