Dian Foley, whose son James Foley was brutally executed in 2014 by IS, said she is worried that without US support, SDF would not have the ability to continue detaining the killers of her son, Olksanda Koteh and Shafi'i Sheikh, who are detained in the centers of North Syria.
"I would ask President (Donald) Trump to remember that these Syrian Kurds are holding these men who targeted and killed our citizens and that we need to help them bring justice to our citizens," Dian Foley told CNN.
The State Department accused Koteh of "possibly involved in mass executions and cruel torture" of Western journalists and aid workers' hostages. According to the Foreign Ministry, Sheikh has acquired a bad reputation as a result of his brutal treatment of prisoners and his execution of prisoners.
Koteh and al-Shafi'i were accused of belonging to the cell, which also included Mohammed al-Amwazi - known as the "jihadist John" - who was killed in a US air strike in 2015.
The group is suspected of beheading 27 people, including British aid workers David Haines, Alan Henning, US citizens James Foley, Stephen Sutlov and relief worker Peter Kasig.
However, officials in North Syria have suggested earlier that Trump's decision could strain the situation in the country, making them unable to continue with the detention of an estimated 800 prisoners currently, according to the Times British newspaper.
Reuters news agency quoted form officials of SDC that the forces led by the Syrian Democratic Forces may not be able to contain IS prisoners in the case if the region was attacked by Turkey.
Dian Foley has made part of her mission to bring Koteh and Sheikh to the United States to try them for their crimes.
"I feel that if we do not hold these people accountable for killing our citizens, if this kind of impunity prevails, there will be a problem for us in the future," she told CNN.
Her efforts are complicated by the fact that this couple is from the United Kingdom - they are among the dozens of foreign IS mercenaries which countries are wrestling over who bears responsibility for them. The US Justice Department did not immediately respond to CNN's inquiry into the case.
"Defenders and officials who were working to bring the couple into the United States have a race against time because of the withdrawal," said Sen. Jane Shain, a Democrat from New Hampshire, who wrote in the Washington Post.
"The sudden and indiscriminate nature of this withdrawal also undermines the role of the United States in holding other war criminals accountable in the region," the report said.
Foley said she was unable to meet administration members because of logistical problems and closures, but she praised their work for helping American hostages abroad.
The US national security adviser John Bolton said protecting the Kurds would be a condition for the US withdrawal from Syria – it is a condition that sparked the wrath of the Turkish President Recep Tayyip Erdogan.
Foreign Minister Mike Pompeo said on Saturday discussions with Turkey that the issue is continuing, but he expressed his confidence that an agreement could be reached.