Trump demand on IS fighters 'difficult to implement'

U.S. President Donald Trump's demand that Europe should "take back" 800 Islamic State fighters will be "extraordinarily difficult to implement," German Foreign Minister Heiko Maas said on Sunday.

Their return would only be possible "when it can be ensured that these people will immediately be put before a court and when they're held in custody," Maas told the ARD television programme "Anne Will."

In order to do that authorities would need information and criminal investigations that could not be guaranteed, he said. "And as long as that's the case, I believe it would be extraordinarily difficult to implement."

People with German citizenship were entitled to return to Germany, he added, but in Syria there was no currently no way of checking their claims, he added.  "And that's why we'll decide with the French, with the British, what to do," he said.

Norbert Roettgen, a prominent member of Chancellor Angela Merkel conservative Christian Democrats and chair of the German parliament's foreign affairs committee, also slammed Trump's request.

"This demand of the American president is not constructive either in tone or content," he told the Monday edition of the Passauer Neuen Presse newspaper. "If you start passing the responsibility back and forth that's not a constructive or promising approach," he continued, adding that the problem of what to do with foreign Islamic State fighters must be tackled together.

Trump on Saturday demanded that Europe "take back over 800 IS fighters that we captured in Syria and put them on trial," threatening that the U.S. would otherwise be forced to release them. "The U.S. does not want to watch as these ISIS fighters permeate Europe, which is where they are expected to go," he wrote on Twitter, adding "Time for others to step up and do the job that they are so capable of doing."

Islamic State is currently on the verge of being dislodged from its last bastion in eastern Syria, after the Kurdish-led Syrian Democratic Forces (SDF) launched an assault last week.

According to the Kurds, there are "hundreds" of foreign Islamic State fighters as well as their wives and children in prisons and refugee camps in northern Syria. The SDF has long been critical of Europe's resistance to repatriating their citizens and welcomed Trump's call earlier Sunday.

According to the German Interior Ministry there are around 270 German women and their children in Syria and Iraq.

Around 1,050 Germans have travelled to the conflict zone since 2013 and about a third of these people have since returned.    (dpa)