PARIS - Islamic State fighters hiding among refugees travelling from Libya to Italy pose a "major risk" to Europe, French Defence Minister Jean-Yves Le Drian said Sunday.

Le Drian said there was an "urgent" need for a political solution to the crisis in Libya to help combat the spread of the Islamic State group (IS), which now has several thousand fighters in the North African country. "Daesh is installing itself," Le Drian told French TV, using the Arabic acronym for the IS group.

"I have been very worried about Libya since September 2014. They are there, nearly 300 kilometres from the coast, and they are spreading."

He said that put IS only 350 kilometres from the Italian island of Lampedusa, the arrival point for thousands of migrants and refugees leaving Libya for the European Union.

"When good weather comes to the Mediterranean, there is the risk that (IS fighters) could make the crossing, mixing in with refugees. It's a major risk," said Le Drian.

"Everyone is aware of the danger of transferring the conflict in the Levant (Syria and Iraq) where we are starting to see some positive elements, to a new conflict in Libya," he said, adding that a political solution was the "only way to eradicate" the problem.

"There must be a government of national unity. There's a serious political process under way, supported by the UN Security Council. I think it's urgent."

Libya has been in chaos since the 2011 ouster of longtime dictator Moamer Kadhafi. It now has two governments and parliaments, with the recognised authorities based in the eastern city of Tobruk and a militia-backed authority in Tripoli.

UN envoy Martin Kobler expressed concerns Wednesday that Libya's political process is slower than the IS group's expansion, after the Tobruk government rejected a proposed unity government.

Meanwhile, support for German Chancellor Angela Merkel's conservative alliance has slumped to its lowest since July 2012 as opposition over her liberal refugee policy grows, a survey showed Sunday, while a right-wing populist party polled a record high.

According to the poll published by the Bild am Sonntag newspaper, public support for Merkel's Christian Democratic Union and sister party Christian Social Union now stands at just 34 percent, down two percentage points.

The Social Democratic Party - the junior partner in Merkel's left-right grand coalition, has also lost ground, shedding one percentage point to 24 percent, according to the poll of 1,638 people conducted from January 21 to 27.

Meanwhile, the populist Alternative for Germany (AfD), which on Saturday sparked a storm by suggesting that police should be allowed to shoot migrants to stop them from entering Germany, scored a record 12 percent, gaining two percentage points on a similar poll published a week ago.

Founded on a eurosceptic platform, the AfD has gone through a leadership split and veered further to the right, with some of its leaders voicing support for the anti-Islamic PEGIDA protest movement.

On Saturday, its chairwoman Frauke Petry said border police "should be able if need be to have recourse to their firearms - as laid down by law."

"No policeman wants to fire on a refugee and I don't want that either. But as a last resort there should be recourse to firearms," said Petry in comments to the Mannheimer Morgen regional daily that drew a flurry of criticism. With 1.1 million asylum seekers arriving in Germany in 2015, concerns are growing over the country's ability to integrate the newcomers.

After a decade in power Merkel has come under fierce pressure to review her open-arms approach towards those fleeing war, with emotions heightened after a rash of sexual assaults in Cologne on New Year's Eve police blamed mostly on North Africans.

While Merkel does not face national elections until 2017, regional elections in three states in March will be a key test of support, with the AfD hoping to pick up seats at her party's expense.

A poll published Friday by news weekly Focus found that 40 percent of respondents want Merkel to resign.

Nevertheless, a subsequent poll commissioned by Focus found that, with 41 percent, Merkel came in top as the politician whom the public believe can best manage the migrant crisis.

Runner up with 38 percent was Bavaria's premier Horst Seehofer, who has been a vocal critic of Merkel's liberal stance. Finance Minister Wolfgang Schaeuble polled 34 percent and Social Democrat chief Sigmar Gabriel with 30 percent.