A removable dispensing closure assembly for an opening in the wall of a container includes an integral plug with a longitudinal passage having an annular flange portion at the outer end adapted to abut against the outer surface of the container wall together with an intermediate portion and an annular lip portion at the inner end sized to insert into the container opening. A flexible tubular member passes through the plug passage and has a normally closed outer end and an open inner end everted over the annular lip portion and back along the periphery of the intermediate portion to form an enlarged flexible end portion having an outer dimension larger than the internal dimension of the container opening whereby the closure assembly can be forcefully inserted into the container opening to effect a fluid-tight seal. Dispensing through the tubular member is effected by selectively opening and closing the passage of the tubular member externally of the container.