PARIS—French President Nicolas Sarkozy described Israeli Prime Minister Benjamin Netanyahu as a "liar" during a recent conversation with President Barack Obama that was overheard by reporters, according to a French website's report of the incident.

"You may be sick of him, but me, I have to deal with him every day," Mr. Obama replied, according to the French site, Arrêt sur Images.

A spokesman for Mr. Sarkozy, a spokesman for Mr. Netanyahu and a White House official declined to comment.

Senior French government officials have criticized Mr. Netanyahu in recent months over his refusal to freeze Israeli settlement construction in Palestinian territories.