The Italian European Parliament vice president said she joined the Renew group to fight back against a populist surge

For a politician so focused on the battles raging outside the European Union, this struggle had come too close to home.

Pina Picierno has spent years warning about Vladimir Putin, championing military aid to Ukraine and building networks with Russian dissidents.

Now the European Parliament vice-president has turned her fire on the Italian Democratic Party, which was until recently her political home.

This month she abandoned the social democratic PD and its S&D grouping in the European Parliament to join Renew Europe, cementing her reputation as one of the sharpest critics of what she sees as a rising populist tendency inside the European centre-left.