In the run-up to inauguration day the dollar showed none of the verve that had taken it higher at the end of last year. Investors' enthusiasm for the Trumponomics that would bring tax cuts and infrastructure spending was overshadowed by their nervousness about the Trumpolitics which threaten swingeing import taxes and trade wars. The dollar lost a net half a cent to the euro and it was down by nearly two cents against sterling.

Theresa May's Brexit speech on Tuesday was sterling's unlikely saviour. Although she said Britain would be leaving the EU entirely, single market and all, her main points had been leaked the previous evening so it did not come as a surprise. Investors were relieved at the idea of a phased implementation and liked the idea that parliament would get a vote on whatever deal is hammered out with Brussels.