Sarkozy had an up-and-down relationship with Gadhafi's regime.
Two months after his 2007 election, Sarkozy's then-wife Cecilia traveled to Libya and helped negotiate the release of Bulgarian nurses and a Palestinian doctor sentenced to death on charges of infecting children with HIV. Their case had strained Libya's relations with the international community.
Later that year, Gadhafi was received in Paris for a formal state visit, pitching his tent near Sarkozy's Elysee Palace despite widespread protests from human rights groups.
Then when Gadhafi's forces cracked down on an opposition movement amid the Arab Spring uprisings last year, Sarkozy quickly became one of Gadhafi's most vociferous critics. Sarkozy led an international push for airstrikes to force Gadhafi from power. Gadhafi was later killed.
Days before the NATO-led airstrikes began in March 2011, one of Gadhafi's sons first leveled the accusations that Libya had once financed Sarkozy's political ambitions.
Although no evidence has emerged that any funding ever took place, website Mediapart reported Saturday it had obtained a 2006 Libyan document signed by Gadhafi's then-intelligence chief Moussa Koussa with an offer by the regime to spend (EURO)50 million ($66 million) on Sarkozy's first presidential bid.
Sarkozy's legal complaint accused Mediapart of "forgery" and "publication of false news."
Rami Al-Shaheibi in Tripoli, Maggie Michael in Cairo and Sylvie Corbet in Paris contributed to this report.