The French Prime Minister faces a grilling in parliament today over accusations he has been involved in a political smear campaign, claims he denies. Dominique de Villepin is facing calls to resign over allegations that he told investigators to target his main rival and possible presidential contender in the ruling party, Nicolas Sarkozy.The controversy, known as the Clearstream affair, is dominating the headlines in France. This at a time when the government is already weakened after having to make a u-turn on a youth jobs law that triggered street protests. President Jacques Chirac and Villepin have denied any involvement in what isclaimed to have been a plot to discredit Sarkozy. It emerged that someone sent accusations to a judge that Sarkozy and other prominent figures channelled illegal funds through the Luxembourg company Clearstream. The claims were later found to be false. Before appearing in parliament today, Villepin is due to answer questions in a morning radio programme.