We demonstrate phase clusterization in a hierarchical network of mutually coupled van der Pole
oscillators. We find that in the system with random initial phases there is a coupling parameter,
which corresponds to intermittent transition from non-synchronous state to synchronous.
Clusterization does not decay if oscillators have non-identical natural frequencies or randomly
distributed initial phases. In this structure, those elements that are placed on the same
hierarchical level have equal phases.