The invention relates to a valve block (1) for a pressurised gas cylinder (20) comprising: an inner gas passage (2) providing fluid connection between a gas inlet opening (10) and a gas outlet opening (11); a gas monitoring system (3) arranged on the inner gas passage (2), making it possible to monitor and/or adjust the flow of gas circulating in said inner gas passage (2); a system for selecting and/or adjusting the flow of gas, comprising a movable operating member (4) which can be actuated by the user and engages with the gas monitoring system (3) in order to monitor and/or adjust the flow of gas exiting via the gas outlet opening (11); an electronic control system (7, 7', 8) making it possible to control an actuator device (5); an actuator device (5) capable of controlling the movement of a mobile mechanical member (6) in response to a control signal output by the electronic control system (7, 7', 8); and a mobile mechanical member (6) acting on the operating member (4) of the system for selecting and/or adjusting the flow of gas, in response to an actuation by the actuator device (5), such as to block or release the mobile operating member (4). The invention also relates to a gas distribution assembly comprising a gas cylinder (20) provided with a valve block (1) according to the invention, protected by a protective cover arranged around at least one portion of said valve block (1).