  We prove the uniqueness of the supersymmetric Salam-Sezgin
(Minkowski)_4\times S^2 ground state among all nonsingular solutions with a
four-dimensional Poincare, de Sitter or anti-de Sitter symmetry. We construct
the most general solutions with an axial symmetry in the two-dimensional
internal space, and show that included amongst these is a family that is
non-singular away from a conical defect at one pole of a distorted 2-sphere.
These solutions admit the interpretation of 3-branes with negative tension.
