A Council Decision of 12 December 1991 "concerning the conclusion of the amendment to the Montreal Protocol on substances that deplete the ozone layer as adopted in June 1990 in London by the Parties to the Protocol" (91/690/EEC) states that, on the most recent scientific evidence a higher degree of control of chlorofluorocarbons and halons is required for adequate protection of the ozone layer than is provided for by the Montreal protocol of September 1987; the same evidence indicates that additional controls should be placed on all other fully halogenated chlorofluorocarbons, carbon tetrachloride and 1,1,1-trichloroethane. To this end, an amendment and an adjustment to the Montreal Protocol were adopted in London (June 1990), only the amendment requiring approval. The Council therefore approves the amendment on behalf of the Community. The text of the amendment, annexed to the Decision, sets out the time periods and percentage reductions in the use of the listed substances. In general these correspond to a reduction, to be achieved by January 1993, to 80% of the 1989 level of consumption and a further reduction, by January 1997, to 15% of the 1989 level. Use of these substances should terminate in January 2000. Special conditions cover basic domestic needs, control of trade with non-signatories, and the situation of developing countries. Control measures, reporting of data, and financial and technical cooperation are also considered.