French President Francois Hollande dramatically announced Thursday he would not seek re-election next year as he bowed to historic low approval ratings after a troubled five years in power.

"I have decided that I will not be a candidate," Hollande said in a solemn televised statement from the Elysee Palace in Paris during which he defended his record.

He conceded that he was unable to unite his deeply divided Socialist party behind his candidacy ahead of the presidential election in April and May next year.

"In the months to come, my only duty will be to continue to lead my country," he said.

Hollande's popularity has hit rock bottom after a term in office marked by U-turns on major policies, terror attacks, high unemployment and embarrassing revelations about his private life.

A new poll on Wednesday predicted he would win just seven percent of votes in the first round of next year's election in April -- strengthening Socialist party critics who view him as a lame duck.

Voter surveys currently tip rightwing Republicans party candidate Francois Fillon to win the election, with the far-right National Front candidate Marine Le Pen seen as his closest challenger.

But with the full range of candidates still unknown and the role of independents such as 38-year-old former economy minister Emmanuel Macron difficult to predict, analysts urge caution about the forecasts.

Divided Socialists

Hollande's withdrawal leaves the field open in the Socialist party which began accepting candidates on Thursday for a party primary race due on January 22 and 29.

Arnaud Montebourg, a leftist former economy minister, has already submitted his name while ambitious Prime Minister Manuel Valls would also be expected to stand.

Valls, unfailingly loyal to Hollande until recently, hinted at the weekend that he might run against his boss in the primary, raising pressure on him to stand aside.

He also spoke out against Hollande in October after the publication of a devastating book called "A President Shouldn't Say That" featuring interviews with the president.

The book was the last straw for many supporters after Hollande was quoted criticising judges, the national football team and even his own government's policies.

'Mr Normal'

The Socialist leader has some of the lowest approval ratings for a French president since World War II.

He took office in 2012 promising to be "Mr Normal" after what were seen as the excesses of the years under president Nicolas Sarkozy, who married supermodel Carla Bruni and was often pictured with millionaire friends.

But his presidency has been anything but normal.

France has faced three major Islamist-inspired terror attacks since January 2015 -- firstly against the Charlie Hebdo magazine, then in Paris in November and in Nice in July.

On economics, Hollande started with a leftist programme that included a wealth super-tax of 75 percent on top-earners but he shifted course mid-way through his term to embrace pro-business reforms.

And his colourful personal life has never been far from the headlines, leading his opponents to claim he has demeaned one of the most powerful political offices in Europe.

In January 2014, celebrity magazine Closer published pictures of him arriving on a scooter at an apartment near his official residence for secret trysts with a French actress, Julie Gayet.

The revelations led to the break-up of Hollande's relationship with partner Valerie Trierweiler who went on to write an eviscerating book which claimed the president mocked poor people as "the toothless".

A mixed legacy

Hollande listed his achievements on Thursday night, saying he had worked to "get France back on track and make it more fair" through reforms to the economy, social security and education.

He pointed to a global accord on climate change signed in Paris last year as part of his legacy, as well as his handling of the terror attacks when he had sought to heal and comfort a wounded country.

On unemployment -- which Hollande had promised to lower before the election -- he admitted that "the results are coming, later than I had promised them, but they are there."

Hollande's decision came on a day when the left-leaning Le Monde newspaper delivered a withering assessment of his time in office.

Le Monde wrote in an editorial that the Socialists risked tearing themselves apart ahead of the presidential election as well as parliamentary polls in June.

"The person who is most responsable is Francois Hollande, who has not given a meaning to his time in office, occupied the job with authority or imposed himself as the legitimate candidate for his party," it said.