Rome, September 17 - Protesters have announced plans to demonstrate outside the Rome headquarters of State broadcaster RAI over possible plans to air a video message prepared by former premier Silvio Berlusconi amid political turmoil after the supreme court upheld a tax-fraud conviction against the ex-premier last month. "Today at 17:30 we will be in Viale Mazzini to deliver the petition to RAI chief Gubitosi," Gianfranco Mascia of the Popolo Viola activist movement announced in an online message. The petition was signed by 122,000 people, he says. Mascia criticized making State resources available to someone who has a criminal record. For weeks there has been speculation about the video message, amid press leaks that Berlusconi has prepared a message announcing his center-right People of Freedom (PdL) party was withdrawing its support from Premier Enrico Letta's left-right government. The PdL is furious with its government alliance partner, the centre-left Democratic Party (PD) of Premier Enrico Letta, which intends to vote for Berlusconi to be stripped of his parliamentary seat on a Senate panel following the tax-fraud verdict. A key vote on the panel is set to take place Wednesday.