French President Nicolas Sarkozy has accused US President George W Bush of failing to take the initiative over the summer conflict in Georgia, BBC reported.
Receiving a prize in France for "political courage", he asked his audience "who defended human rights?" after the war erupted in August.
"Was it the president of the United States... Or was it France?" he asked.
Mr Sarkozy led a mission to Moscow that resulted in a ceasefire between Georgia and Russia.
Picking up the prize, awarded by Politique Internationale magazine, at a ceremony at his own Elysee Palace in Paris, Mr Sarkozy suggested the American president did not want to stake his credibility on a push for peace.
"When on 8 August someone had to leave for Moscow or Tbilisi, who defended human rights?" he asked rhetorically.
"Was it the president of the United States, who said 'This is unacceptable'? Or was it France which kept up the dialogue" between the leaders of Russia and Georgia, he asked, in a speech covered by the French AFP news agency.
"I remember the American president's call the day before our departure for Moscow: 'Don't go there, they [the Russians] want to go to Tbilisi, they're 40km away. Don't go, [just] condemn it'.
"I did go, along with [French Foreign Minister] Bernard Kouchner, and, as if by coincidence, while we were there the ceasefire was declared," Mr Sarkozy said.
Mr Sarkozy will lead an EU delegation in talks with Russian officials in Nice on Friday, after which the two sides are expected to resume negotiations on a new partnership agreement.
The negotiations were frozen by the EU over Russia's role in the conflict.
The conflict in the region began on 7 August when Georgia tried to retake its breakaway region of South Ossetia by force after a series of lower-level clashes with Russian-backed rebels.
Russia launched a counter-attack and the Georgian troops were ejected from both South Ossetia and Abkhazia, a second breakaway region, days later.