An electrical circuit breaker with separable electrical contacts includes a fixed electrical contact, a mobile electrical contact, that can be displaced between open and closed positions and including several electrical contact fingers, arranged aligned along a row and that can be displaced relative to the mobile electrical contact, several bearing members, each associated with a contact finger to exert a force on this contact finger in order to displace it. The bearing members associated with the contact fingers situated in lateral end zones of the row exhibit a higher stiffness than the bearing members associated with the contact fingers situated in a central part of the row.