London (CNN Business)The British pound dropped sharply on Thursday after a key UK government minister resigned, plunging the Brexit process into deep uncertainty and hiking the risk of a chaotic rupture with the European Union. Brexit Secretary Dominic Raab said in a statement on Thursday that he "cannot in good conscience support the terms proposed for our deal" to leave the European Union. The pound fell 1.6% against the dollar to below $1.28 following the resignation.
