Florence Mayor Matteo Renzi, who lost to Pier Luigi Bersani in the Democratic Party (PD) primaries and is considered his main rival, broke the truce he declared with his party leader after the election and accused him of being “stuck”.

Renzi said Bersani has been “humiliated by the arrogance of the Five Star Movement” and called to stop courting it and instead seek a temporary deal with Silvio Berlusconi’s People of Freedom Party (PDL) – an idea which many in the PD view with horror – or go to the polls if this fails.

Young, centrist and sharing some of the anti-establishment views of Beppe Grillo, Renzi is seen as a strong candidate that could unite the centre-left, but had until now kept silent and bought time in order to strengthen his position.