We present 12CO(2-1) observations of the submillimetre galaxy ALESS65.1 performed with the Australia Telescope Compact Array (ATCA) at 42.3 GHz. A previous Atacama Large Millimeter Array study of submillimetre galaxies (SMGs) in the Extended Chandra Deep Field South detected C ii 157.74 μm emission from this galaxy at a redshift of z = 4.44. No 12CO(2-1) emission was detected but we derive a firm upper limit to the cold gas mass in ALESS65.1 of . The estimated gas depletion time-scale is <50 Myr, which is similar to other high-redshift SMGs, and consistent with z > 4 SMGs being the likely progenitors of massive red-and-dead galaxies at z > 2. The ratio of the C ii, 12CO and far-infrared luminosities implies a strong far-ultraviolet field of G 0 103, as seen in Galactic star-forming regions or local ultraluminous infrared galaxies (ULIRGs). The observed is high compared to local ULIRGs and, combined with , it is consistent with ALESS65.1 either having an extended (several kpc) C ii emitting region or lower than solar metallicity.