High-profile defection hits Renzi's party.

It's been an unusually long period of stability in Italian politics since Renzi took charge but today Giuseppe Civati, a former close ally, announced he was leaving the PD party. This week, around 50 PD rebels refused to back a reform of the electoral law which was approved by parliament.

Polls still show Renzi's party's popular backing is strong at 36%.

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