The French national referendum on the E.U. constitutional charter is to take place on May 29, the office of President Jacques Chirac announced Friday. The announcement comes after Chirac consulted with leaders of every French political party and after the two houses of Parliament, sitting in joint session on Monday, approved amendments to the French Constitution that cleared the way for a referendum on the charter. Most surveys show that if the referendum were held now, the E.U. charter would be approved by a substantial majority of French voters. However, it is opposed by a number of politicians on the right and left, and a lively campaign lies ahead. That campaign will also include debate about Turkey's eventual E.U. membership, since politicians opposed to Ankara joining the Union have threatened to use the E.U. charter referendum to press their point. The E.U. constitutional charter must be approved, either by parliamentary vote or referendum, by every one of the Union's 25 member nations.