July 28 (Bloomberg) -- Italian Prime Minister Romano Prodi won't agree to changes in a plan to reform parts of the country's pensions system, a spokesman said, in response to newspaper reports that the program may be amended.

Prodi will back the agreement reached on pensions with Italy's largest labor unions, the prime minister's spokesman, Silvio Sircana, said in an e-mailed statement today.

Four ministers met Prodi yesterday to express disapproval of the plan and gained Prodi's consent that parts may be changed when the accord is sent to parliament to be approved as law, newspaper Corriere della Sera reported today.

Alessandro Bianchi of the Communist Party, Alfonso Pecoraro Scanio of the Greens, Paolo Ferrero of the Refounded Communists and Fabio Mussi of the Democrats of the Left went to the meeting and are the most radical in the governing coalition, the newspaper reported.

Earlier this month Prodi won union support for a gradual increase in the pension age, ending a seven-month dispute that divided his government.

The government plans to phase in a four-year increase in the minimum retirement age, currently 57, by 2013, replacing an existing law that boosts the age to 60 next year. The measure sacrifices 10 billion euros ($13.6 billion) in savings achieved by the current law, Labor Minister Cesare Damiano said at the time.

The four ministers want to introduce into the agreement more worker-protection clauses and eliminate some parts allowing part- time and flexible work contracts, Corriere said.

To contact the reporter on this story: Anthony DiPaola in Rome at adipaola@bloomberg.net.

Last Updated: July 28, 2007 10:25 EDT