asked the Secretary of State for Energy, pursuant to the statement on the Sleipner gas contract, Official Report, 11 February, column 23, what percentage of the increased gas reserves of 6·2 trillion cubic feet is (a) probable, (b) proven, (c) in the southern basin, (d) in the northern basin, (e) condensate gas and (f) in fields larger than 0·5 and 0·75 trillion cubic feet, respectively.

Details of the full breakdown of my Department's latest estimates of United Kingdom gas reserves will be given in the 1985 report to Parliament on the development of oil and gas resources (the Brown Book).