Sarkozy faces a summer of discontent as French unions flex muscles over pension plans

The centre-right government of President Nicolas Sarkozy  wants employees to work 41 years before qualifying for a full pension.

They currently need to work for 40.

In an attempt to defuse the crisis, the government has committed to keeping the minimum retirement age at 60 - even though many of France's neighbours, including Britain and Italy, have raised it to 65.

In a separate action, fishermen blocked the country's ports in a row over rising petrol prices.

Protest: French fishermen block truck traffic and access to the refinery of oil giants Total at La Mede near Marseille today

Mr Sarkozy has shown little sign of backing down over pensions but has shown more sympathy towards France's 24,000 fishermen, who say their fuel costs have doubled in a year.

Schools remained open, one week after a widely followed strike over cuts in education staffing, meaning it was business as usual for much of France.

However, union leaders said the success of their protest would be measured by how many people turned out for the rallies, with 500,000 expected in Paris alone for the main march.

"The goal is not to get everyone out on strike," said Bernard Thibault, head of the powerful CGT union.

"The scale of the protests will show that the government will have to review its plans under pressure," he added.

More than one million people took to the streets during the last such demonstration against pension reform in 2003 and anything less today would weaken the union position.

Besides the pensions protest, Sarkozy also faced disputes in other sectors on Thursday, with port workers striking over plans to privatise part of their industry and fishermen still disrupting shipping in their fight against rising fuel costs.

A year after Sarkozy was elected on a platform of sweeping economic reforms, his approval rating has tumbled because of concern over the rising cost of living and disapproval over his abrasive, sometimes flashy, style of government.

Unions hope to tap into this discontent and force a U-turn over pensions. But the government insists that rising life expectancy coupled with weak public finances means the pensionable age must rise, as it has elsewhere in Europe.

Looking to appease union anger, it has however committed to keeping the minimum retirement age to 60 against 65 in many of its neighbours, including Britain and Italy.

Opponents say the real problem is that many companies systematically get rid of workers in their 50s, who then collect handsome benefits until they can formally retire, and say the government should tackle this problem first.

But Sarkozy shows little sign of backing down, and has promised to unleash a fresh wave of reforms to improve the efficiency of the spendthrift state in the coming months.

"The past has convinced Nicolas Sarkozy that the strategy of step-by-step reform is not the right one. When you stumble on the first step, you never take the second one," right-leaning newspaper Le Figaro said in an editorial on Thursday.

Sarkozy's first major showdown with the unions was last November, when transport workers staged a 9-day strike against plans to scrap special pension rights enjoyed by some state sector workers. The government eventually won the battle.