Italy under Silvio Berlusconi is moving towards authoritarianism, a veteran voice of the left has declared, as the opposition broke off talks on constitutional reform with the centre-right government on Friday.

The “honeymoon” period that the prime minister has enjoyed since his election victory in April appears to be over, with Mr Berlusconi accused of fixing a law to halt his own corruption trial and initiating a constitutional conflict with Giorgio Napolitano, Italy’s president.