An oxo-bridged diruthenium(III) complex containing pyrazolato and pyrazole ligands is stable against ascorbic-acid reduction, induces apoptosis (60%, 48 h) against HeLa cells at 10 μM level and exhibits promising anti-angiogenic activity at its sub-cytotoxic concentrations. Other mononuclear ruthenium(III) complexes containing pyrazole ligands [Ru(pz)₄X₂]⁺ exhibit dual anti-angiogenic and cytotoxic properties.