Sarkozy, whose country holds the presidency of the 27-member EU, made the comment in discussions with lawmakers from his conservative party, said the official, who attended the meeting. The official spoke on condition of anonymity because the discussions were private.
The Lisbon Treaty was crafted to smooth out and speed up the bloc's decision-making and bolster its international profile. It was thrown into serious doubt when Ireland rejected it in a June 12 referendum. Sarkozy, who pushed heavily for the treaty, is expected to travel to Ireland next week to help look for solutions to the crisis.
Ireland, Foreign Minister Micheal Martin sought to downplay the significance of Sarkozy's reported comments.
"President Sarkozy was speaking at a private party meeting," Martin said. "He like any other democrat is entitled to his own particular view as to what happens next. It will be for the Irish people to decide how we proceed post-Lisbon. We ultimately will take the decision."
Sarkozy's office says he will be in "listening mode" when he travels to Ireland on July 21. But Irish opposition chiefs - virtually all of whom campaigned for a "yes" vote in the failed referendum - accused the French leader of insensitivity and foolishness. They noted that, when French voters help to shoot down a proposed EU constitution in 2005, they were not put under pressure to vote again.
Eamon Gilmore, leader of the opposition Labour Party, said Sarkozy had "seriously put his foot in it" and questioned why he would make any such comments right before coming to Ireland.
"We were given to understand that one of the principal reasons for the president's visit to Ireland next week was to allow him to hear the views of Irish people as to what should now be done," Gilmore said. "However, if he has already made his mind up on this issue, it will be a rather hollow listening."
The nationalist Sinn Fein, the only significant party to campaign against the treaty, said the only option open to the EU was to negotiate a new treaty, not to repackage Lisbon for a second Irish vote.
"In the month since the Irish people voted overwhelmingly to reject the Lisbon Treaty, we have listened to a succession of EU leaders lining up to try and bully and coerce us into doing what they want," Sinn Fein lawmaker Aengus O Snodaigh said. "The fact is that the people have spoken and the Lisbon Treaty is dead."
French Foreign Minister Bernard Kouchner took a diplomatic tone at a European Parliament committee on Tuesday, saying, "We have to remain levelheaded and let the Irish think this through.
"I don't think we should force (them) ... It is possible to find a way out of the impasse," he said. "The Irish 'no' is not Ireland's failure, it's a European failure."