US Central Command chief General Kenneth McKenzie on Monday visited Kurdish-led allies in northern Syria for the first time since taking up the post. Gen McKenzie – who oversees US operations in the Middle East – succeeded Gen Joseph Votel in March. Gen Votel's departure came only days after the Kurdish-led Syrian Democratic Forces (SDF) recaptured the last patch of territory from ISIS in eastern Syria with US support. After the months long campaign, Syria's Kurds now hold thousands of ISIS suspects in jails and tens of thousands of women and children in overcrowded camps for the displaced in parts of north and north-eastern Syria that they control. They have repeatedly urged foreign nations to repatriate around 1,000 alleged foreign fighters and tens of thousands of non-Syrian women and children linked to the group, but most countries have been reluctant. During his visit, Gen McKenzie and SDF chief Mazlum Abdi discussed "the problem of camps and ISIS detainees held by the SDF", the Kurdish-led alliance said. They also spoke of co-ordination between the US-led coalition and the SDF to carry on hunting down ISIS sleeper cells, it said. The extremist group has continued to claim deadly car bombings and arson attacks on key wheat fields in SDF-held territory, despite its territorial defeat. SDF spokesman Mustafa Bali said the meeting had taken place in Kobane, on Syria's northern border with Turkey and from which Kurdish forces drove out ISIS in January 2015. He posted a photo on Twitter of both commanders shaking hands. "Several important issues including a proposed safe zone, future co-operation between the SDF and anti-ISIS coalition and situation of jihadists and their families were discussed," he quoted Mr Abdi as saying, using an alternative acronym for ISIS. US President Donald Trump last year threatened to withdraw all US troops from northeast Syria, sparking fears among Kurds they would be exposed to a long-threatened Turkish attack. After his announcement, Mr Trump attempted to ease tensions by speaking of a 30-kilometre "safe zone" on the Syrian side of the border. In an interview with broadcaster TGRT Haber, Turkish Foreign Minister Mevlut Cavusoglu said he hopes an agreement on the safe zone will be reached after talks on Monday with US special envoy for Syria James Jeffrey, who is visiting Ankara. But, he warned, if the planned safe zone is not established soon, then Turkey will send troops across the border. A small number of American soldiers remain in north-east Syria and Washington has pushed for increased military support from other coalition members. Gen McKenzie said Monday that numbers had been reduced "considerably" but did not share exact numbers. "The key thing right now is to make sure that local security is established so that we can prevent the resurgence of ISIS," he told the local North Press Agency. "We're going to help them to do that, and then our plan's going to be to leave," he said, without giving a specific time frame.