(see related stories on vote for new president) Rome, April 17 - Beppe Grillo said on Wednesday that Stefano Rodota' will be his 5-Star Movement's presidential candidate after investigative journalist Milena Gabanelli and war-zone doctor Gino Strada refused. Rodota', 82, is a constitutional lawyer, former head of Italy's privacy authority and former Communist and centre-left MP. He came third in an online vote of M5S members staged Monday behind Gabanelli and Strada. "After Milena Gabanelli and Gino Strada declined I called Rodota', who agreed to stand and will be the candidate voted by the M5S," comedian-turned-politician Grillo, whose anti-establishment movement won around a quarter of the vote in February's inconclusive general election, said via his Twitter account. Lawmakers from the Lower and Upper House of parliament and representatives of Italy's regional governments will start voting for President Giorgio Napolitano's successor on Thursday. "Stefano Rodota' is (over) 80 years old and he's been out of the loop for a bit, but when he heard about the candidacy he started jumping and said 'I'm available'," Grillo said at a rally. "Maybe he's too old, but we're supporting him". Earlier on Wednesday accused centre-left leader Pier Luigi Bersani of causing the "suicide" of the Italian Republic after he had talks with ex-premier Silvio Berlusconi over possible names to be the next head of state. Democratic Party chief Bersani presented a shortlist of three candidates, former centre-left premiers Giuliano Amato and Massimo D'Alema and former centre-left Senate Speaker Franco Marini, who are being "considered" by Berlusconi, according to ANSA sources. Grillo accused Bersani of holding a two-man primary with "psycho-dwarf" Berlusconi. He predicted that the pair were set to agree to have D'Alema or Amato elected president. He also insinuated that this deal would provide "judicial guarantees" for Berlusconi, who is involved in several criminal cases, including a trial into allegations he paid for sex with an underage prostitute. "For Bersani it is the suicide of the Republic for which he, and only he, is responsible," Grillo said in his blog, which gave life to the M5S in 2009. Grillo had hinted on Tuesday that he might be willing to soften his position, after staunchly refusing to back a centre-left-led government to end Italy's post-election deadlock, if Bersani backed the M5S's presidential candidate. Rodota' is seen as a candidate who may also be able to garner support from parts of the PD.