Waste container including a base defining a waste-receiving compartment, a lid movably attached to the base and movable between a first position covering a waste insertion opening and a second position in which it does not obstruct the waste insertion opening and a support portion including an aperture through which a bag is placed into the compartment. An obstruction mechanism includes an actuator and an obstruction member having at least one part that selectively engages with the bag at a location below the support portion. The actuator is manually and/or automatically rotatable to cause rotation of the obstruction member between a first position in which the obstruction member is in a first plane not obstructing insertion of waste into the bag and a second position in which the obstruction member is in a second plane obstructing insertion of waste into the bag.