A surgical instrument, comprising: a housing; a shaft extending distally from the housing; an end effector assembly disposed at a distal end of the shaft, the end effector assembly including first and second jaw members, at least one of the first or second jaw members moveable relative to the other from a spaced apart position to an approximated position; a knife slidably disposed within the shaft; a movable handle operably coupled to the housing and movable relative thereto between an initial position and a compressed position; a trigger operably coupled to the housing and movable relative thereto between an un-actuated position and an actuated position; a drive assembly operably coupled between the movable handle and the end effector assembly such that movement of the movable handle from the initial position to the compressed position moves the drive assembly to thereby move the at least one of the first or second jaw members from the spaced-apart position to the approximated position, the drive assembly including a drive housing; and a linkage including an apex pivotably engaged to the housing and first and second ends operably coupled to the trigger and the knife, respectively, such that movement of the trigger from the un-actuated position to the actuated position moves the first end of the linkage to thereby pivot the linkage about the apex and move the second end of the linkage to deploy the knife relative to the end effector assembly, the pivoting of the linkage about the apex defining a path of movement; wherein, in the initial position of the movable handle, a portion of the drive housing intersects the path of movement of the linkage to inhibit pivoting of the linkage to deploy the knife, thereby inhibiting movement of the trigger from the un-actuated position to the actuated position. a housing; a shaft extending distally from the housing; an end effector assembly disposed at a distal end of the shaft, the end effector assembly including first and second jaw members, at least one of the first or second jaw members moveable relative to the other from a spaced apart position to an approximated position; a knife slidably disposed within the shaft; a movable handle operably coupled to the housing and movable relative thereto between an initial position and a compressed position; a trigger operably coupled to the housing and movable relative thereto between an un-actuated position and an actuated position; a drive assembly operably coupled between the movable handle and the end effector assembly such that movement of the movable handle from the initial position to the compressed position moves the drive assembly to thereby move the at least one of the first or second jaw members from the spaced-apart position to the approximated position, the drive assembly including a drive housing; and a linkage including an apex pivotably engaged to the housing and first and second ends operably coupled to the trigger and the knife, respectively, such that movement of the trigger from the un-actuated position to the actuated position moves the first end of the linkage to thereby pivot the linkage about the apex and move the second end of the linkage to deploy the knife relative to the end effector assembly, the pivoting of the linkage about the apex defining a path of movement; wherein, in the initial position of the movable handle, a portion of the drive housing intersects the path of movement of the linkage to inhibit pivoting of the linkage to deploy the knife, thereby inhibiting movement of the trigger from the un-actuated position to the actuated position. <EOS>