The present invention relates to a kit for whitening teeth comprising a multi-phase oral composition for whitening teeth preferably comprising a water-in-oil emulsion. The oral compositions comprises from about 0.002% to about 5% by weight of an aqueous phase； a predominant proportion of a hydrophobic phase； at least one oral care active agent in the aqueous, phase, wherein the active agent is a bleaching agent and the ratio of the bleaching agent in the aqueous phase to the net concentration of the bleaching agent in the oral composition is at least 20. The kit comprises further an electromagnetic radiation source capable of directing electromagnetic radiation with one or more wavelengths in the range from 200nm to 1700 nm toward at least one tooth.The present invention also relates to the use of the kit for whitening teeth and/or removing stain from tooth surfaces as well as to a method of whitening teeth, removing stain from tooth surfaces or both. The use and the method are based on the oral composition and the electromagnetic radiation source as presented herein.
