A conjecture on the large complex frequency asymptotic behaviour of the resolvent kernel of the electric field integral equation operator is presented. The conjecture is based on a detailed examination of the corresponding large frequency behaviour of a matrix approximant to the operator. From this analysis it is concluded that the resolvent decays exponentially on a sequence of concentric circular contours of increasing radius threading between poles in the left half plane. The decay rate is proportional to the distance between observation and source points.