Global leaders have been sending their congratulations to Liz Truss - but in the international media, there have been snarkier remarks.
In France, meanwhile, she has been branded 'Not The Iron Lady' - former UK PM Margaret Thatcher's nickname - but 'The Iron Weathercock'.
This is a reference to Ms Truss's changing views on the UK leaving the European Union - she went from opposing it before the 2016 referendum, to supporting it afterwards, saying in July that "some of the portents of doom didn't happen".
It's believed the term was first coined in ''Les Echos'' in July - but has since caught on among some commentators. Like ''Les Echos'', Italy's Corriere della Sera compared Truss to Thatcher - but described the new leader's speeches as more "robotic".
Speakdating c’est dores-et-déjà plus de 1 000 activités et leçons,
plus de 40 000 exercices, là tout prêts, dans votre poche.