A container closure assembly comprising: a foldable pouring spout of plastics material having a first end providing a dispensing aperture and a second end provided with an annular mounting flange configured for mounting the foldable pouring spout on a container neck; and a closure member of plastics material removably sealingly engageable across the dispensing aperture to selectively allow or prevent dispensing of container contents through the dispensing aperture; wherein the closure member is integrally formed with a securing ring which is attached to the closure member by a frangible connection; the securing ring being snap-fittingly engageable over and around the mounting flange with the frangible connection intact and the thus assembled closure assembly being snap-fittingly engageable over and around the container neck; a groove extending circumferentially about the annular mounting flange and which is open in an axial direction opposite to the first end of the foldable pouring spout for reception of the container neck in such snap-fitting engagement; wherein the circumferentially extending, axially open groove is defined in part by a radially outer wall having a proximal portion lying towards the first end of the foldable pouring spout and a distal end portion lying away from the first end of the foldable pouring spout; characterized in that the radially outer wall comprises a central flexure zone of reduced radial width relative to the proximal and distal end portions (54, 56) and which interconnects the proximal and the distal end portions, whereby the distal end portion is hingeingly deflectable relative to the proximal portion, between a radially outer position for extraction of the foldable pouring spout from a mold tool, and a radially inner position for engagement in an annular undercut in a radially outer surface of the container neck; wherein when the securing ring is snap-fittingly engaged over and around the mounting flange, the distal end portion is held in the radially inner position; and wherein the distal end portion of the radially outer wall comprises a chamfer at its radially inner side and which extends radially inwards towards the first end of the foldable pouring spout for guiding the closure assembly into snap-fitting engagement with the container neck. a foldable pouring spout of plastics material having a first end providing a dispensing aperture and a second end provided with an annular mounting flange configured for mounting the foldable pouring spout on a container neck; and a closure member of plastics material removably sealingly engageable across the dispensing aperture to selectively allow or prevent dispensing of container contents through the dispensing aperture; wherein the closure member is integrally formed with a securing ring which is attached to the closure member by a frangible connection; the securing ring being snap-fittingly engageable over and around the mounting flange with the frangible connection intact and the thus assembled closure assembly being snap-fittingly engageable over and around the container neck; a groove extending circumferentially about the annular mounting flange and which is open in an axial direction opposite to the first end of the foldable pouring spout for reception of the container neck in such snap-fitting engagement; wherein the circumferentially extending, axially open groove is defined in part by a radially outer wall having a proximal portion lying towards the first end of the foldable pouring spout and a distal end portion lying away from the first end of the foldable pouring spout; characterized in that the radially outer wall comprises a central flexure zone of reduced radial width relative to the proximal and distal end portions (54, 56) and which interconnects the proximal and the distal end portions, whereby the distal end portion is hingeingly deflectable relative to the proximal portion, between a radially outer position for extraction of the foldable pouring spout from a mold tool, and a radially inner position for engagement in an annular undercut in a radially outer surface of the container neck; wherein when the securing ring is snap-fittingly engaged over and around the mounting flange, the distal end portion is held in the radially inner position; and wherein the distal end portion of the radially outer wall comprises a chamfer at its radially inner side and which extends radially inwards towards the first end of the foldable pouring spout for guiding the closure assembly into snap-fitting engagement with the container neck.