A weak rotationally resolved absorption band of (CO)-C-12-O-18 has been identified from photographic VUV spectra and assigned to the k(3) Pi(nu = 3) <-- X(1)Sigma(+) (nu = 0) forbidden transition. The experimentally determined hand origin and upper state rotational constant are in close agreement to that derived from isotopic scaling. A consideration of the intensity structure of the hand suggests that the band gains its intensity mainly through a k(3)Pi (nu = 3)-E-1 Pi (nu = 0) interaction. This is the first direct observation of the k(3)Pi state for (CO)-C-12-O-18. (C) 2005 Elsevier B.V. All rights reserved.