An electrosurgical system for sealing and cutting biological tissue comprising: a signal generator configured to impart an alternating current, AC, sealing signal between a set of sealing electrodes (506, 508) and to impart an AC cutting signal between a set of cutting electrodes (510, 512); a first controller configured to determine impedance of biological tissue disposed between the set of sealing electrodes (506, 508) while the AC sealing signal is imparted between the set of sealing electrodes (506, 508); wherein the first controller is configured to control the signal generator to impart a continuous AC sealing signal between the set of sealing electrodes (506, 508) starting before imparting the AC cutting signal in response to the impedance of biological tissue disposed between the sealing electrodes (506, 508) reaching a first impedance threshold value, a second controller is configured to control the signal generator to impart the AC cutting signal between the set of cutting electrodes (510, 512) during discrete pulse time intervals; wherein the first controller is configured to determine impedance of biological tissue disposed between the set of sealing electrodes (510, 512) while the AC cutting signal is imparted between the set of cutting electrodes (510, 512); wherein the first controller is configured to control the signal generator to halt the AC sealing signal between the set of sealing electrodes (506, 508) in response to impedance of the biological tissue disposed between the set of sealing electrodes (506, 508) reaching a second impedance threshold value; wherein the second controller is configured to control the signal generator to halt the AC cutting signal; and wherein the AC sealing signal is in phase with the AC cutting signal. a signal generator configured to impart an alternating current, AC, sealing signal between a set of sealing electrodes (506, 508) and to impart an AC cutting signal between a set of cutting electrodes (510, 512); a first controller configured to determine impedance of biological tissue disposed between the set of sealing electrodes (506, 508) while the AC sealing signal is imparted between the set of sealing electrodes (506, 508); wherein the first controller is configured to control the signal generator to impart a continuous AC sealing signal between the set of sealing electrodes (506, 508) starting before imparting the AC cutting signal in response to the impedance of biological tissue disposed between the sealing electrodes (506, 508) reaching a first impedance threshold value, a second controller is configured to control the signal generator to impart the AC cutting signal between the set of cutting electrodes (510, 512) during discrete pulse time intervals; wherein the first controller is configured to determine impedance of biological tissue disposed between the set of sealing electrodes (510, 512) while the AC cutting signal is imparted between the set of cutting electrodes (510, 512); wherein the first controller is configured to control the signal generator to halt the AC sealing signal between the set of sealing electrodes (506, 508) in response to impedance of the biological tissue disposed between the set of sealing electrodes (506, 508) reaching a second impedance threshold value; wherein the second controller is configured to control the signal generator to halt the AC cutting signal; and wherein the AC sealing signal is in phase with the AC cutting signal.