Dominique Strauss-Kahn on Tuesday denied knowing the women he had orgies with were prostitutes and said paying for sex would be too great a risk for a man who was head of the International Monetary Fund.

The silver-haired economist once tipped for the French presidency faced a barrage of questions on the organization of sex parties as he took the stand for the first time charged with "aggravated pimping" for allegedly aiding and abetting prostitution.

Jean-François Girault, Director of the Department of the Middle East and North Africa at the French Foreign Ministry, held talks Monday in Rome with Maronite Patriarch Beshara al-Rahi about the outcome of his latest Mideast tour, especially in relation with the presidential void in Lebanon.

Girault and al-Rahi also discussed means to end the presidential crisis, “the needed efforts that must be exerted in Lebanon and the role that must be played by the friendly countries, topped by the Holy See and France,” according to a statement issued by the Maronite Patriarchate's press office.

The EU has agreed to postpone new sanctions against Russia to give time to see if a four-way Ukraine peace summit Wednesday makes progress, French Foreign Minister Laurent Fabius said.

"The principle of the sanctions will be kept, but their implementation will depend on the situation on the ground," Fabius told reporters in Brussels. "We will assess the situation again next Monday."

Police said Monday they came under fire as they rushed into a housing estate in the French city of Marseille after residents alerted them that hooded people had shot "Kalashnikovs" in the air.

The outbreak of violence in La Castellane, an estate known as a drug trafficking hotspot, came just hours before Prime Minister Manuel Valls visited the southern port city to hail the progress made in fighting crime.

French police detained six people Sunday suspected of recruiting potential jihadists, just days after another operation saw five charged on similar grounds, Interior Minister Bernard Cazeneuve said.

France is slowly recovering from the January 7-9 Islamist attacks in Paris that left 17 people dead but remains jittery after incidents such as Tuesday's knife attack on three soldiers outside a Jewish community centre on the French Riviera.

French President Francois Hollande's newfound popularity after the Paris attacks faced its first major test Sunday as a member of his ruling Socialist party battled against a far-right National Front candidate in a tense by-election.

The first round of the poll last Sunday in the eastern Doubs district -- called after Socialist lawmaker Pierre Moscovici left for Brussels to take office as Economic Affairs Commissioner -- saw FN candidate Sophie Montel come first with close to a third of the vote.

German Chancellor Angela Merkel on Saturday pushed a new peace bid to end the Ukraine conflict, warning that sending weapons to government forces fighting pro-Russian rebels would not stop the bloodshed.

Fresh from overnight talks in Moscow with French President Francois Hollande to thrash out a new peace plan, Merkel said success was far from assured but it was essential to try.

French anti-terrorist prosecutors on Friday launched an investigation into an Islamic State group video that called for fresh attacks against France, a judicial source said. 

In the video posted online on YouTube on Tuesday, nearly a month after Islamist attacks in Paris, an unidentified, masked jihadist is seen surrounded by militants calling on French Muslims to quit their country for IS' self-proclaimed "caliphate", which covers parts of Iraq and Syria.

Already under the cosh for a scandal involving 52 kilo-grammes of cocaine, the Paris criminal police department has suffered a further stain on its reputation after a top boss was suspended over alleged leaks.

Known in France by its address "36 quai des Orfevres" and immortalized in the novels of Belgian crime writer Georges Simenon, the department has suffered months of embarrassment.

French Ambassador Patrice Paoli has denied that Paris was drafting a U.N. Security Council Resolution against Hizbullah as a top official in New York warned that the situation in the border area between Lebanon and Israel remains “very fragile.”

France “calls for the protection of Lebanon's sovereignty, its territorial integrity and Resolution 1701,” Paoli said in remarks published in An Nahar daily on Friday.