This is not the first time Berlusconi has tried to reform pensions

The unions, which have more than 11 million members, have called for a four-hour walk-out on 24 October.

Mr Berlusconi in a television address warned that government plans to reform Italy's expensive welfare system were "necessary, fair and wise".

He said his government was determined to make changes that would provide Italians with greater "security and well-being".

ITALY'S PENSIONS DILEMMA Italians fear a poor old age View from an Italian village

But union leaders dismissed Mr Berlusconi's appeal, and said the issue had been blown out of proportion.

"We ask all workers, young people and pensioners to take to the streets and defend a system which is not in trouble," the leaders of the CGIL, CISL and UIL said in a joint statement.

"There is no pensions emergency. The government... is dramatising the pensions problem."

Italy - like many European countries - is attempting to find ways to support its ageing population, which is the result of low birth rates and longer life expectancy.

At present paying pensions takes up 15% of GDP.

Changes afoot

Officially, Italy's retirement age is 65 for men and 60 for women.

The real retirement age is much lower because of a system which allows a pay-out once an employee has made 35 years of contributions and is at least 57-years-old.

The government proposes offering Italians incentives to work longer, and then from 2008 permitting people to retire only when they are 65 or have made at least 40 years of contributions.

In April 2002, Mr Berlusconi was forced to back down over labour market reform after the three unions staged a strike, with a quarter of Italian workers taking part.

His first government collapsed in 1994 over the pensions issue.