BofA analysts argued that the reaction function of the BoE, which is supposed to show how they balance growth and inflation indicators in their decision about rates, has been changing over time, "becoming more unpredictable." Some analysts said press reports that the United States was to delay trade talks with the UK over post-Brexit concerns regarding the Northern Ireland protocol might add further uncertainty to the pound. A U.S. administration official on Thursday said the country's failure to remove tariffs on UK steel and aluminium had no connection to concerns about post-Brexit trade rules affecting Northern Ireland.