Ten-year gilt yields dropped to 0.947%, down 1 basis point on the day and their lowest since June 2017, while five-year yields sank to the lowest since December 2017 at 0.705%.

British ministers expect May to make a statement by mid morning, following growing pressure from many Conservative Party lawmakers for her to announce the end of her premiership and open the door to a successor who would take a tougher line on European Union exit talks.