Mr Sarkozy says he want Syria to play a positive regional role
Syria's President Bashar al-Assad has said it would be a catastrophe if a peaceful solution could not be found to the Iranian nuclear row.
Mr Assad was speaking after a meeting in Damascus with French President Nicolas Sarkozy aimed at improving bilateral ties.
The leaders also held discussions on Syria's relations with Israel.
Relations between Paris and Damascus plummeted after the murder of former Lebanese PM Rafik Hariri in 2005.
Syria's critics accuse Damascus of being behind the assassination, a charge Syria has firmly denied.
Mr Sarkozy's two-day visit to Syria - which was formerly ruled by France under a mandate of the League of Nations - is the first by a Western head of state in five years.
He hosted Mr Assad in July and correspondents say he appears determined to bring Syria, a long-time foe of the US and Israel, back into the international fold.
During the Paris summit, Syria and Lebanon, an important ally of France, agreed to open embassies in each other's capitals for the first time since the 1940s.
In a joint news conference with Mr Sarkozy on Wednesday evening, Mr Assad said that any attack on Iran over its nuclear programme would be a catastrophe.
He said it was clear there was no trust between Iran and other countries but that Syria would continue to work towards a solution through conversations with both Iran and France.
In a newspaper interview earlier on Wednesday, Mr Sarkozy said that Syria could "provide an irreplaceable contribution to solving Middle East issues".
"It is important that Syria plays a positive role in the region," he told Syria's al-Watan newspaper, adding that peace in the Middle East "passes through" Syria and France.
Mr Sarkozy also used Wednesday's joint press conference to offer French support for direct peace talks between Israel and Lebanon, when the time was right.
Mr Assad said his country was "in the process of building foundations for the peace talks" and would need help from the US and others for direct negotiations to take place.
The BBC's Bethany Bell in Damascus says that both parties have talked about a new era in relations but that Mr Sarkozy will be under pressure from his Western allies to show that engagement with Syria can work.
And Syria must decide how flexible they can be on the key contentious issues, our correspondent adds.
Meanwhile, Israeli officials have warned that Europe should be "very careful in its relationship with Syria".
"Except for a slight change in tone, Syrian policies have not changed," said foreign ministry spokesman Yigal Palmor, criticising Syria's connections with the Palestinian movement Hamas and the Lebanese Shia militant group Hezbollah.
On Thursday, the two presidents will be joined by top officials from Turkey and Qatar for talks on Lebanon and Syria's indirect peace talks with Israel.
Ankara has been mediating for several months in the Israeli-Syrian talks, while Qatar brokered a deal in May to resolve Lebanon's prolonged political crisis.