PARIS -- It could happen only in France. The president of the Republic is running for re-election as the opposition candidate while his main challenger is defending the government's record over the past five years.

This paradoxical situation ahead of the two-round presidential poll in April and May, followed by legislative elections in June, is the result of a constitution that provides for both a presidential elected by direct suffrage and a prime minister who is normally the leader of the largest party in Parliament. In 1995, Jacques Chirac won the presidency in his third attempt. He inherited a large center-right parliamentary majority, but after two years on office, he called a legislative election to seek popular backing for government policies. That rebounded against him and brought a victory for the left, forcing the neo-Gaullist Chirac to appoint Socialist leader Lionel Jospin as prime minister at the head of a government that includes Communists and Greens as well as Socialists.

Now Chirac and Jospin face one another again in the presidential contest. They have been jousting since the left's electoral victory in 1997, but now the gloves are off after both men formally declared their candidacies earlier this month. They will tussle over policies, with law and order and economic issues likely to take front stage.