ENQUEST PLC, Production and Development Update.

EnQuest is today updating its production targets for the full year 2011. The S7 production well in the Conrie field, discovered earlier this year, and the S8Z well in area 6 of the Don Southwest field both started production during August 2011. The S7 Conrie well came on production at lower than expected rates. The S8Z well started production at the expected initial rate, but has declined more quickly than anticipated. EnQuest is in the process of testing and assessing the well results. EnQuest does not expect a material change in ultimate recovery of reserves in the Don Southwest field and is studying whether a further well or sidetrack is needed.