The European Union risks a populist-nationalist “nightmare” by the middle of the next decade unless centrists can win greater public backing for the European cause, the liberal leader Guy Verhofstadt has said.

Elections this May could herald a big shake-up of the European parliament. The duopoly of centre-right and centre-left is expected to lose its majority for the first time in 40 years of direct elections although Emmanuel Macron’s La République En Marche (La REM) is expected to win seats for the first time, boosting liberal forces.