The present invention relates to an oxidative hair colouring and bleaching composition comprising an oxidizing agent, a source of carbonate ions, and an alkalising agent, wherein the composition comprises at least 4% by weight of hydrogen peroxide or a source of carbonate ions, utilised at pH 9.5 and below and wherein said composition is free of a source of radical scavengers which result in improved lift and lightening for blonde shades, excellent dye deposition and colour and improved grey coverage. Moreover, the compositions of the present invention also exhibit low odour and deliver a high level of lift and lightening equal to the currently utilised ammonia/peroxide systems, whilst reducing the concentration of peroxide and reducing the hair fibre damage.
