The recurring theme in the United States is of a president, hamstrung by the controversy surrounding his administration and at odds with the Senate. The latter was not particularly in evidence last week but investors were unnerved by another rearrangement of the White House deckchairs when Donald Trump fired his new director of communications and hired a new chief of staff. Some reasonable US economic data were not enough to offset that negative: the dollar lost two cents to the euro and two thirds of a cent to the pound.

Sterling came unstuck too. It started well enough, sharing the lead with the euro on three successive days, but was derailed on Thursday by the Bank of England's cautious - even pessimistic - assessment of the UK economic outlook. The bank sees wages being outpaced by inflation for many months to come. It also now looks possible that there could be no interest rate increase until after Britain leaves the EU.