French Foreign Minister Laurent Fabius said Monday he plans to return to Vienna this week as world powers work to finalize a landmark deal on Iran's nuclear program.

"I will be back in Vienna this week," Fabius told reporters in New York where he was to attend a U.N. event on climate change.

A man who beheaded his boss in France has denied any religious motivation, investigative sources said Monday, muddying efforts to pin down the reasons for an attack which bore the hallmarks of a jihadist act.

Yassin Salhi, 35, on Sunday confessed to decapitating his employer and pinning his severed head to the fence of a gas factory in eastern France in a macabre display that included two Islamic flags.

France has deported 40 foreign imams for "preaching hatred" in the past three years, a quarter of them in the last six months, Interior Minister Bernard Cazeneuve said Monday.

The minister vowed to clamp down on mosques and preachers inciting hatred after a suspected Islamist beheaded his boss during an attack on a gas factory last week.

The gruesome "selfie" taken by a man who has confessed to beheading his boss during an attack on a gas factory in France was sent to Syria, sources close to the investigation said Sunday.

The news emerged as Yassin Salhi, 35, was being transferred from France's second city of Lyon to Paris for questioning by specialized anti-terrorist police.

French authorities were transferring the man suspected of beheading his boss in an alleged jihadist attack to P

aris on Sunday, as it emerged he sent a macabre "selfie" of the decapitation.

French police were grilling a suspected Islamist Saturday about an attack in which the man displayed his boss's severed head, as it emerged he may have sent a "selfie" of the decapitation.

Sources close to the investigation said the suspect, Yassin Salhi, a 35-year-old married father-of-three sent a picture of him with the severed head via the WhatsApp messaging service.

Iran has condemned the jihadist attacks in Tunisia, Kuwait and France, saying they were "contrary to the teachings of Islam," in statements released Saturday by the foreign ministry.

The killings were not apparently coordinated, but the Islamic State group claimed the atrocities in Tunisia and Kuwait, just days before the first anniversary of it declaring a "caliphate" in Iraq and Syria.

France and Spain pledged Friday to launch a new effort at the U.N. Security Council for action to stop barrel bomb attacks in Syria, which rights groups describe as a leading killer in the war.

The council adopted a resolution in February 2014 demanding an end to the bombings that the West says are carried out by the Damascus regime using helicopters to drop barrels rigged with explosives on civilian districts.

Italy raised its terror alert level on Friday after deadly attacks in France, Tunisia and Kuwait.

"No country is without risk, we have raised the level of alert to re-sensitize those units charged with protecting sensitive places," Interior Minister Angelino Alfano said.

Spain raised its terror alert level from medium to high on Friday after deadly attacks in France, Tunisia and Kuwait, its Interior Minister Jorge Fernandez Diaz said.

"Considering the proximity of our country to the places where some of these attacks took place, it has been proposed to raise the anti-terrorist alert" from three out of five, or 'medium', to four or 'high', he told a news conference.