Other changes would streamline parliamentary procedures, devolve powers to the regions and cut taxes.
Berlusconi told supporters that the 'People of Liberty' ('Popolo Della Liberta'; PDL) party - the union of the Forza Italia (Go Italy!) movement he founded 15 years ago with the right-wing National Alliance (AN) - already commanded 44% of the vote and would get stronger.
The new party's first big political test will be the June 2009 European elections, with the PDL expected to become the largest member of the European People's Party (EPP) following the poll.
"We aim to reach 51%. A great party like ours must never be satisfied," the 72 year-old media tycoon said in his closing address amid a flag-waving crescendo of applause in a rock concert atmosphere.
"There are still so many Italians who can join us to make Italy truly modern, free and European," said Berlusconi, who is leading his fourth government and has ruled Italy for seven of the last 15 years.
The smaller AN was a distant heir to Benito Mussolini's fascist party which, under the leadership of former foreign minister Gianfranco Fini, has progressively moved towards the centre over the last two decades.
The two parties already ran under the same Party of Freedom banner at the 2008 election which returned Berlusconi to power and, along with the regionalist Northern League, formed the backbone of the centre-right ruling coalition.
But the new rightist party should be able to steer clear of those kinds of comparisons, after the xenophobic right-wing Northern League of Umberto Bossi chose not to join the PDL.
Raft of promises
Amid a raft of promises, Berlusconi vowed to toughen recruitment criteria for teachers and university professors, subject all schools to a system of public evaluation and make English obligatory throughout high school education.
"We will revitalise and enrich the constitution," Berlusconi said, in order to make government decision-making faster and more efficient. "The prime minister has to be given greater powers, real powers," he added.
With the centre-left opposition unable to achieve unity or direction after its rout at the last election, Berlusconi's popularity has risen despite the impact of the global crisis on Italy, the euro zone's third largest economy.
"We will come out of this crisis well and nobody will be left behind," Berlusconi said. "We will change Italy and defend democracy and freedom."
(EurActiv with Reuters.)
