High-voltage circuit breaker filled with insulating gas having a main axis A, comprising: - two arcing contacts (12, 16) facing axially each other and radially surrounded by an insulating nozzle; - two main contacts (14, 18) facing axially each other and arranged radially outside of the insulating nozzle, each of the main contacts (14, 18) being assigned to one of the arcing contacts (12, 16), wherein an insulating gas flowing from a storage chamber and heated by an electric arc in a region between the two arcing contacts (12, 16) is partitioned into a first gas flow and a second gas flow of opposite directions, wherein the first gas flow and second gas flow are conducted outside of the insulating nozzle from opposite directions at least partially toward a main gas chamber surrounding the main contacts (14, 18), wherein the first gas flow flows toward the main gas chamber through a first intermediary gas chamber and the second gas flow flows toward the main gas chamber through a second intermediary gas chamber, wherein it the second gas flow flowing in the second intermediary gas chamber is partitioned in a first portion directed to the main gas chamber and a second portion directed to an exhaust gas chamber, wherein the second intermediary gas chamber is in fluidic communication with the main gas chamber via at least one first opening and is in fluidic communication with the exhaust gas chamber via at least one second opening, characterized in that the overall section of the at least first opening is inferior to the overall section of the at least second opening, such that the first portion of the second gas flow is smaller than the second portion of the second gas flow. - two arcing contacts (12, 16) facing axially each other and radially surrounded by an insulating nozzle; - two main contacts (14, 18) facing axially each other and arranged radially outside of the insulating nozzle, each of the main contacts (14, 18) being assigned to one of the arcing contacts (12, 16), wherein an insulating gas flowing from a storage chamber and heated by an electric arc in a region between the two arcing contacts (12, 16) is partitioned into a first gas flow and a second gas flow of opposite directions, wherein the first gas flow and second gas flow are conducted outside of the insulating nozzle from opposite directions at least partially toward a main gas chamber surrounding the main contacts (14, 18), wherein the first gas flow flows toward the main gas chamber through a first intermediary gas chamber and the second gas flow flows toward the main gas chamber through a second intermediary gas chamber, wherein it the second gas flow flowing in the second intermediary gas chamber is partitioned in a first portion directed to the main gas chamber and a second portion directed to an exhaust gas chamber, wherein the second intermediary gas chamber is in fluidic communication with the main gas chamber via at least one first opening and is in fluidic communication with the exhaust gas chamber via at least one second opening, characterized in that the overall section of the at least first opening is inferior to the overall section of the at least second opening, such that the first portion of the second gas flow is smaller than the second portion of the second gas flow.