Former Italian Prime Minister Matteo Renzi | Franco Origlia/Getty Images Italy’s left splits with Matteo Renzi “We want to build an open movement … that is also the beginning of a center-left renewal.”

Left-wing rebels who quit Italy’s ruling party over clashes with former Prime Minister Matteo Renzi have formed a new political party — the Progressive and Democratic Movement (DP).

Uniting left-leaning defectors from the ruling Democratic Party (PD) and part of the Sinistra Italiana (the Italian Left), the DP was founded on Saturday, according to Agence France-Presse.

"We want to build an open movement ... that is also the beginning of a center-left renewal," it said in its founding manifesto.

It is headed by the ruling party's former leader in parliament, Roberto Speranza, and Enrico Rossi, the head of the Tuscany region.

Former PD boss Pier Luigi Bersani and another former prime minister, Massimo D'Alema, are also among the supporters, according to the report.

The new party could possibly spoil the center-left party’s chances at the next elections, which have to take place by February next year, but which Renzi would like to bring forward to June or September.

Renzi resigned from his post as prime minister in December after losing a key constitutional referendum. He was replaced by Paolo Gentiloni, the foreign minister in his government.