Romano Prodi, Itali's centre-left leader, has rejected the idea of forming a German-style "grand coalition" with his rival Silvio Berlusconi who was defeated in the general election. "We came into this election with a set coalition, and the electoral law has alloted us a number of seats in the Chamber (of Deputies) and in the Senate which will allow us to govern," Prodi told journalists on Tuesday outside his campaign headquarters in Rome.Prodi's Union alliance won the weekend elections, taking control of both the chambers of parliament, according to full results released on Tuesday, but Berlusconi has so far refused to concede defeat. Berlusconi, prime minister since 2001, claimed that "a great many irregularities" might have marred results, and that a pivotal race for six Senate seats - representing Italians living abroad - could be invalidated. That vote had swung the upper chamber to Prodi with four of the six seats going his way.