Around three-quarters of Germans reject a new anti-Islamic movement that has drawn thousands on to the streets in recent months for weekly populist protests, a poll showed Friday.

Just 17 percent said they found the so-called group, "Patriotic Europeans Against the Islamization of the Occident" (PEGIDA), good, according to the Politbarometer poll for ZDF television.

Scores of German police raided alleged Islamist sites in Berlin early on Friday, arresting two men suspected of being part of a group planning to carry out an attack in Syria, police said.

Around 250 police officers carried out the raids on 11 sites in the German capital, arresting the two men of Turkish origin aged 41 and 43, police said in a statement.

Police on Thursday arrested a German-Tunisian man suspected of having joined the Islamic State (IS) jihadist group in Syria, the federal prosecutor's office said.

The 26-year-old suspect, named as Ayub B., is thought to have entered Syria via Turkey last year to be trained in IS combat and recruiting, before returning to Germany in August, the German prosecutor said in a statement.

Chancellor Angela Merkel said Thursday she understood many of the concerns that drove people to join populist protests, even though she opposes Germany's new anti-Islamic movement.

She reiterated that "prejudice, coldness, even hatred" motivated organizers of the so-called "Patriotic Europeans Against the Islamisation of the Occident" (PEGIDA) marches and urged citizens to stay away from their rallies.

Germany's foreign minister said Thursday no more deadlines must be missed in the Iran nuclear negotiations which had entered "a decisive phase", speaking at a meeting with his Iranian counterpart.

"We must now use the newly opened time window, we must leave nothing undone to reach the solution that has eluded us in recent years," Frank-Walter Steinmeier said before the talks with Iranian Foreign Minister Mohammad Javad Zarif.

Chancellor Angela Merkel pledged Thursday to heighten security measures against Islamist militants following the Paris attacks, while vowing that Germany would not be divided by extremism of any kind.

"Hate preachers, violent delinquents who act in the name of Islam, those behind them, and the intellectual arsonists of international terrorism will be rigorously fought with all legal means at the disposal of the state," she said.

An anti-Islamic movement that is growing in Germany has opened a branch in Spain following last week's attacks in France, the group said Wednesday.

The Spanish wing of PEGIDA was launched on Twitter on January 8, the day after an attack by Islamist gunmen on French satirical magazine Charlie Hebdo in Paris that left 12 people dead including some of the country's best-loved cartoonists.

Germany will tighten a foreign travel ban on known Islamists to stop them heading to war zones such as Syria, the cabinet decided Wednesday, a week after the Charlie Hebdo attacks.

The law is the first of a host of previously planned security measures which Chancellor Angela Merkel's government wants to speedily pass through parliament in the coming weeks following the bloodshed in France.

Bestselling French novelist Michel Houellebecq will promote his new book imagining a France under Islamic rule next week in Germany after suspending a French tour in the wake of the Paris attacks, his publisher said Tuesday.

He is to present the book, whose German translation will hit bookstores Friday, in the western city of Cologne Monday, French publishing house Flammarion told Agence France-Presse.

Three Ukrainian civilians and a soldier were reported killed on Tuesday in the latest wave of fighting across the country's separatist  east.

The Ukrainian military said another 10 soldiers were wounded in Grad rocket and mortar attacks by pro-Russian insurgents based around the eastern industrial city of Donetsk.