The United States has no intention to end its alliance with the Syrian-Kurdish militia, a senior administration official said on Tuesday, effectively pushing back on Ankara's demand that Washington stop supporting fighters it sees as hostile. YPG, the main element of the Syrian Democratic Forces and a US ally against ISIS, has kept thousands of extremists in jails across north-eastern Syria and has also overseen camps where relatives of fighters have sought shelter. Ankara views the YPG as a terrorist group. Turkey launched its offensive into north-eastern Syria against the Kurdish YPG militia last month, following Mr Trump's decision to move US troops out of the way. "There is no intention for that co-operation to end," A senior administration official said ahead of a meeting between US President Donald Trump and his Turkish counterpart Recep Tayyip Erdogan on Wednesday. The Turkish offensive prompted concern over the fate of the prisoners, with Turkey's Western allies and the SDF saying it could hinder the fight against ISIS and aid its resurgence.The official said around 10,000 ISIS detainees and their families in nearby camps present a big security risk, even though the US-allied Syrian-Kurdish SDF was fully capable of keeping them secure. "It's not a particularly secure situation," the official said. "Its a ticking time bomb to simply have the better part of 10,000 detainees, many of them foreign fighters," he said, and repeated Washington's stance that they should be repatriated to their countries. ISIS has lost almost all of its territory in Iraq and Syria. Its former leader Abu Bakr Al Baghdadi was killed in a US raid last month. World leaders welcomed his death, but they and security experts warned that the group, which carried out atrocities against religious minorities and horrified most Muslims, remained a security threat in Syria and beyond. Allies have been worried that ISIS militants could escape as a result of Turkey's assault against the YPG, who have been holding thousands of the group's fighters and tens of thousands of their family members. "We are very confident about the ability of SDF to secure all of the detention facilities that they are holding people in and to manage Al Hol camp, but again, we don't want to put any of this under any risk for any kind of humanitarian, counter-terrorism and other reasons," the official said.