(ANSA) - Rome, February 23 - Silvio Berlusconi's Forza Italia party demanded answers on Tuesday after Italian media reported on new Wikileaks files that suggest a special unit of the United States National Security Agency (NSA) listened in on the telephone conversations of the former premier during his last term as the head of government. "What happened seems to be an extremely serious thing," said Forza Italia Senate whip Paolo Romani after daily newspaper La Repubblica and weekly magazine Espresso carried the reports. "It's serious that the NSA took the liberty to take wiretaps at the highest level on Italian territory and did not inform the Italian government which, when faced with our questions, has always said that this is not true.
    It seems to me that the executive must now give a clear response". Berlusconi has frequently said there was plot to cause his third government to collapse late in 2011, when Italy risked a Greek-style financial meltdown.