Abstract: Motivated by the analogy between nearly-parallel G₂-structures and 6-dimensional NK-geometry we study 6-dimensional Nearly-Kähler admitting a unit Killing vector field. We provide a double reduction procedure exibiting, at least locally, a link with the class of Kähler surfaces with constant eigenvalues of the Ricci tensor. In the global case we show that the unique possible geometry is, up to a finite cover, that of the 3-symmetric space S³ x S³.