Describing France as "one of the rare countries where there is such a lack of hope," the man who lost the presidency to Socialist leader Francois Hollande in 2012 said he had had no choice but to return to politics.
"Can I say: France is collapsing, people don't believe in politics anymore, my political family (opposition UMP party) is divided like never before — Ok then I get it, I'll stay at home?," he asked in a television interview.
"Not only do I want (to come back), but I don't have a choice."
The 59-year-old announced his return on Friday on Facebook after months of speculation, setting the scene for a battle among leading centre-right opposition figures for the 2017 general election end-game as they try and put behind in-fighting and scandals that have torn the UMP party apart.
Alain Juppe, who served as defence and foreign minister under Sarkozy, and Francois Fillon, who was prime minister during the former president's five-year term, have both announced they plan to give him a run for his money.
While Sarkozy has said he will stand for the presidency of the UMP in November, Juppe and Fillon are looking further ahead to the party's presidential primaries in 2016.
Sarkozy defends record
Sarkozy's return to politics comes at a time when France is mired in a deep crisis as Hollande struggles with zero-growth, record high unemployment, a bulging deficit and record popularity lows.
The former president defended his own record in office from 2007 to 2012, during which unemployment rose to close to ten percent at the height of the financial crisis.
In 2008, "the worldwide crisis struck France," he said. "It was a crisis that affected every country without exception and every sector.
"In 2014, it is the crisis in France that can tip Europe into bankruptcy. That's new," he warned.
In an interview with the JDD weekly earlier on Sunday, Sarkozy pledged to completely reform the struggling UMP party if elected as its head.
"I am going to change the name of the party, put in place a new organization, install a new generation of people and bring back members and donors to straighten out the accounts," he was quoted as saying.
"If I succeed in this new group, they (Juppe and Fillon) will not be able to catch up with me."
Responding to the challenge, the 69-year-old Juppe told a radio and television programme that "the match has begun."
"Some are trying to make people believe that I will not go through with this. Well I'm going to prove it," he said, hours before outlining his plan for France in a blog post that touched on growth, education, Europe and national unity.
Fillon, meanwhile, told supporters "it's not about saviours for me, it's about ideas," in a thinly-veiled allusion to Sarkozy, whose comeback is perceived by some as the only way to re-unite a party that has fallen far from its glory days.
Myriad of legal woes
Sarkozy is expected to be crowned UMP head with little resistance in November.
But looking ahead to a possible presidential run in 2017, he has a much longer row to hoe.
Polls suggest Juppe is the favourite among the French even if Sarkozy remains the most popular within his own camp.
And a myriad of ongoing legal investigations that involve Sarkozy in one form or another are still lurking in the background.
He was charged in July with corruption and influence-peddling related to his alleged attempt to interfere in a judicial case.
There are also legal questions around the financing of his 2007 and 2012 campaigns that could come back to bite him.
In his television interview, Sarkozy dismissed his legal woes.
"Do you think that if I had something to hide, I would expose myself to a return to politics like today?" he asked.