Phase separation, ferromagnetism and magnetic irreversibility in La1−xSrxMn1−yFeyO3

► Low-field magnetic susceptibility of La1−xSrxMn1−yFeyO3 is investigated. ► Coexistence of ferromagnetism and magnetic irreversibility is observed. ► This is connected to influence of two different magnetic subsystems. ► Both of them exist due to nanosize ferromagnetic particles in paramagnetic matrix. ► Such effect of phase separation is an intrinsic property of manganites.