Breaking a long silence since losing May's presidential election to Socialist Francois Hollande, Sarkozy said he had spoken at length to Syrian opposition leader Abdulbaset Sieda this week and they agreed on the need for foreign intervention in the uprising against Syrian President Bashar al-Assad.
"They noted a total convergence in their views on the seriousness of the Syrian crisis as well as the need for rapid action by the international community to avoid massacres," said the statement signed by Sarkozy and Sieda, who is president of the Istanbul-based Syrian National Council.
"They agreed that there are great similarities with the Libyan crisis," said the statement.
After a three-month hiatus from public life, Sarkozy's sortie, and his 40-minute telephone talk with Sieda, appeared designed to raise pressure on Hollande to engage more openly with Syrian opposition groups.
It came days after French intellectual Bernard-Henri Levy, who prodded Sarkozy to help Libya's rebels last year and became his unofficial adviser in the crisis, slammed Hollande's approach in a newspaper interview.
The French government, which holds the rotating chair of the U.N. Security Council for August, has said Fabius will chair a ministerial meeting of Council members on Aug. 30 focusing mainly on the humanitarian crisis in Syria, with the diplomatic stalemate over concrete action to stop the violence persisting.
Western powers have urged Syrian President Bashar al-Assad to step down, but Russia and China have vetoed Security Council resolutions that would have condemned his government and opened the way to U.N. sanctions against it.
Hollande has not sought to circumvent the United Nations as Sarkozy did with Libya.
While Foreign Minister Laurent Fabius has had frequent contact with Syrian opposition leaders since June, Hollande has shied away from getting too involved, only meeting Sieda briefly during a Friends of Syria meeting in Paris in early July.
That month, Sarkozy was quoted by le Parisien daily as criticising Hollande's policy toward Syria, saying: "I was criticised on Libya but at least I acted."
Sarkozy was quick to embrace Libyan rebels at the height of the crisis there, becoming the first Western leader to recognise them. He spearheaded efforts to assemble an international military coalition which bombed forces loyal to Gaddafi, strengthening rebels who eventually overthrew him a year ago.
But in contrast with isolated Libya, Western powers are leery of intervention in Syria due to Assad's alliances with Russia and Iran and Syria's position at the heart of sectarian and ethnic divisions that radiate across the Middle East.
Sarkozy's conservative UMP party also chimed in on Syria.
"Why is Francois Hollande... doing less than Sarkozy? Why has he decided not to intervene? Because of fear? Because of amateurism? Because he doesn't know how to decide?" UMP official Philippe Juvin said in a statement.