The present disclosure provides a ringspinning system for producing a yarn. It is provided a the ringspinning system comprising a bobbin holder for holding a bobbin from which a first filament is supplied, a drafting stage for drafting the first filament together with a second filament, which is fed to the drafting stage, and a spindle, the ringspinning system further contains at least one sensor for detecting a breakage of the first and/or second filament and/or a roving comprising the first and second filament, which roving comes out of the drafting stage, and a clamp assembly comprising a clamp for fixing the second filament in the case that the sensor detects the breakage, wherein the clamp is provided adjacent the bobbin holder. It is further provided a method for stopping the supply of filaments to a drafting stage of a ring spinning system.