The invention relates to a solid or liquid propellant (2) tank (1) for a thruster, the tank (1) comprising means for forming a gas (9) in the tank, the tank (1) having an opening (4) of surface area S for the extraction of a flow (20) of the propellant gas from the tank (1). According to the invention, the tank (1) comprises a propellant gas flow on-off control system comprising a grid (6) arranged opposite the opening (4) of the tank (1), a first thermal regulation system (11, 21) for heating the gas (9) in the tank and a second thermal regulation system (12, 22) for heating the grid (6), said grid (6) including holes of total surface area greater than the surface area S of the opening of the tank (1).