A surgical instrument including a handle assembly, a safety mechanism, an elongated body portion and a head portion is disclosed. The handle assembly includes a stationary handle, an approximation mechanism, and a firing trigger. A lever of the safety mechanism is movable between a first position where the firing trigger is prevented from being actuated, and a second position where the firing trigger is able to be actuated. A first jaw member of the head portion is movable in relation to a second jaw member of the head portion between spaced and approximated positions. Movement of the first jaw member in relation to the second jaw member from the approximated position towards the spaced position causes the lever of the safety mechanism to move from its second position to its first position.