(By Denis Greenan). Rome, March 21 - The leaders of the anti-establishment 5-Star Movement (M5S) on Thursday asked the president of Italy to either hand them the premiership or control over two important parliamentary commissions, the COPASIR secret service commission and the commission that oversees state broadcaster RAI. M5S leaders made the announcement after exiting meetings with President Giorgio Napolitano about the formation of a new government to break through the nation's political gridlock. The party, led by comedian-turned-politician Beppe Grillo, holds the balance of power in parliament after capturing a huge protest vote last month. M5S Senate Whip Vito Crimi and House Whip Roberta Lombardi told reporters: "We're the biggest single party in the House and we deserve to run the government. Otherwise we want the commissions". Grillo himself has not expressed interest in becoming premier, since he did not run for election because he carries a manslaughter conviction from a car accident and is thus ineligible to hold office. The rabble-rousing comic and activist did not speak to reporters after the meeting, continuing a boycott of the nation's media. But Crimi said that Grillo had "kept Napolitano awake", a remark for which he later apologised. The president's spokesman said Grillo "hadn't realised how tough Napolitano was, and agreed not to call him Morpheus (the God of Sleep) any more". Grillo later said on his blog that the M5S would not support the current parliament and would only support proposals that suit its platform. "The M5S will not agree to any confidence in political or pseudo-technocrat governments with the support of familiar fig leaves," said Grillo on his blog. "The M5S instead will vote for every bill that fits with our platform". Grillo says that members of his party were deceived into voting for centre-left "fig leaf" candidate Pietro Grasso as House Speaker respectively after 11 M5S members broke the party line in order to block centre-right candidates. Grasso left his job as national anti-Mafia prosecutor to run for the centre-left Democratic Party (PD), whose coalition has a comfortable majority in the House but is 20 seats short of one in the equally powerful Senate. Grillo initially threatened to "excommunicate" the errant voters but in the end relented after saying they "fell into a trap". The M5S were the first group to talk to Napolitano on the last day of the president's consultations Thursday. They were followed by ex-premier Silvio Berlusconi's People of Freedom (PdL) party which called for a grand coalition with the PD while ruling out PD leader Pier Luigi Bersani as premier. Bersani, who is meeting with Napolitano later Thursday, is expected to be handed an "exploratory mandate" to form a government but most recent polls say he will fail in his bid. Napolitano is likely to try to form a "government of the president", pundits say, to enact essential reforms such as changing Italy's much-criticised electoral law to increase the likelihood of a clear winner emerging. That would pave the way for fresh elections within a year or so, with Bersani bowing out and the younger, more centrist and media-savvy Florence Mayor Matteo Renzi tipped to take over the PD's helm.