President Nicolas Sarkozy and his challenger Francois Hollande have gone head-to-head in their only TV debate of the French election campaign.

Mr Sarkozy has defended his economic record, stressing that France has not had one term of recession since 2009 under his leadership.

But Mr Hollande said France was going through a “serious crisis” and struggling with slow growth.

Opinion polls suggest Mr Hollande has a lead of seven percentage points.

However, the president is seen as a formidable debater while his Socialist rival lacks experience of government office.

The BBC’s Chris Morris says the debate was a feisty performance with plenty of angry exchanges – including both candidates accusing each other of lying.

But, he adds, neither candidate landed a knock-out blow – which may be to the advantage of Mr Hollande, the favourite for Sunday’s polls.

Mr Hollande said he would work to help those in need, saying that those “with privileges” had been protected under Mr Sarkozy.

“I will be a president for justice, because we are going through a serious crisis that hits in particular the most modest of us, the hardest working people, those who are the most vulnerable.”

He accused Mr Sarkozy of failing to take responsibility for the economic difficulties that France was suffering, blaming it instead of the global economic crisis.

“With you it’s very simple: it’s never your fault,” Mr Hollande said.

Mr Hollande said unemployment levels were “a record” and referred to the downgrading of France’s credit rating.

Lashing back at Mr Hollande, President Sarkozy said France had done better than other European countries in coping with the economic climate.

“What is the country to not have known one quarter of recession since 2009 – it is France,” Mr Sarkozy said.

He rejected Mr Hollande’s proposed stimulus programs, insisting that France had to cut spending and debts.

The president also accused Mr Hollande of representing only the unions, rather than all of France.

“It’s all very nice to talk about uniting people, but it has to be put into practice,” he said.

Mr Hollande also said he would be firm on demands made by the Muslim community, saying he supported France’s ban on face-covering veils and would not allow separate hours in swimming polls for men and women.

Mr Sarkozy has similarly criticised demands for special treatment from France’s Muslim community.

The debate is being broadcast live by several channels and is expected to have a maximum running time of two-and-a-half hours.

About a third of France’s 63 million people were set to watch the event, billed variously by newspapers as The Last Duel and The Final Confrontation.

Mr Sarkozy has attacked Mr Hollande for refusing to hold three election debates instead of one but there has been just one debate per presidential election since 1974, apart from in 2002 when Jacques Chirac refused to debate with the far right’s Jean-Marie Le Pen.

A key moment in Mr Sarkozy’s 2007 debate with Segolene Royal – Mr Hollande’s former partner and mother of his children – came when he told the Socialist candidate to “calm down”. She repeatedly refused to do so, saying some anger was “perfectly healthy”.

Wednesday’s showdown was being presented by two French TV anchors, Laurence Ferrari of TF1 et David Pujadas of France 2.