Sarkozy made the announcement on Monday in an extract of his new book called "Everything for France," to be published later this week.

"I have decided to be a candidate for the 2017 presidential election. I felt I had the strength to lead this battle at a troubled time in our history," the president between 2007 and 2012 wrote.

The 61-year-old will have to win his opposition Republican Party's nomination in November primaries to go on the 2017 ballot. He will face competition from a dozen other contenders, including former prime minister Alain Juppe, who is currently ahead in the polls.

Sarkozy's campaign is expected to center around immigration and security at a time when the country faces the threat of further terror attacks, and there is a renewed debate over the place of Islam in society.

"The next five years will be filled with danger but also with hope," he said.

Tapping into discontent among the right, he has issued scathing criticism of Socialist President Francois Hollande over his handling of immigration and security. Hollande, whose approval ratings have dipped into the teens, has not said whether he will seek another term.

The "top battle" for France was over how "to defend our lifestyle without being tempted to cut ourselves off from the rest of the world," said Sarkozy, naming five key challenges facing France.

Republicans will have to fend off the far-right National Front leader Marine Le Pen, who places among the top presidential candidates in opinion polls.

Sarkozy lost to Socialist Francois Hollande in 2012 after his first term.

He was able to make a political comeback 2014, securing the leadership of the UMP conservative party. The party has since changed its name to the Republicans.

cw/jil (AFP, AP, Reuters)