A top Italian court on Wednesday overturned a law granting Prime Minister Silvio Berlusconi immunity from prosecution, allowing trials for corruption and tax fraud to resume in Milan and prompting immediate calls for his resignation. The decision by the Constitutional Court dealt Berlusconi one of the most serious blows in his 15-year-long battle with the Italian judiciary and added to a list of problems that already includes a sex scandal that has dominated headlines for months. The billionaire businessman-turned-politician dismissed any suggestion of resignation. "Nothing will happen, we will go forward," the premier told reporters in front of his residence in Rome. "The trials they will hurl at me in Milan are real farces," he said. "I will detract some hours from taking care of the government to go there and show them to be liars." The ever-combative premier said he felt "invigorated" by the challenge and ended his brief statement by shouting "Long live Italy! Long live Berlusconi!" The law was pushed through by Berlusconi's conservatives in 2008 when he faced separate trials in Milan for corruption and tax fraud tied to his Mediaset broadcasting empire. The law granted immunity from prosecution while in office to the country's four top office holders - the premier, president of the republic and the two parliament speakers. The proceedings against Berlusconi were suspended as a result of the law, drawing accusations that it was tailor-made for the premier. Berlusconi has denied all charges, and his lawyers had argued in court on Tuesday that he could not be a defendant and at the same time serve as premier. But the 15-judge Constitutional Court said that after two days of deliberations it had found the legislation violated the principle that all are equal before the law. It also rejected the measure on formal grounds because it was not passed with the lengthy procedure that must be used for any legislation concerning the constitution. "I hope that today, in light of the court's decision, the premier will stop making laws for his own use, resign from his job and be what he has resisted being for the past 15 years: the defendant," said Antonio di Pietro, a member of the opposition and a former prosecutor. Berlusconi has a history of legal troubles stemming from his private interests but he has been either acquitted or cleared because the statute of limitations had expired. Reforms Minister Umberto Bossi, a key government ally, told reporters as he left Berlusconi's Rome residence that the premier had no plans to push for early elections. In the Milan corruption trial, Berlusconi was accused of ordering the 1997 payment of at least $600,000 to British lawyer David Mills in exchange for the lawyer's false testimony at two hearings in other corruption cases in the 1990s. While Berlusconi's portion of the trial was frozen when the immunity bill was passed, the proceedings continued for Mills. In February, he was convicted of corruption and sentenced to 4Â½ years in prison. Mills, the estranged husband of Britain's Olympics Minister Tessa Jowell, has maintained his innocence and said he would appeal. Berlusconi faces the tax fraud charge in a trial over Mediaset's purchase of TV rights.