American-allied Kurdish fighters say withdrawal will undo achievements against Islamic State, accuse Washington of failing to honor commitments

White House says American soldiers 'will not support or be involved in the operation,' makes no mention of the fate of allied Kurdish fighters

Washington says Ankara's obtainment of anti-aircraft missile system may endanger American warplanes

Officials from Jerusalem said to have pressured Washington behind the scenes to exclude Ankara from fighter jet program in bid to preserve military qualitative edge

Washington excludes NATO ally after it buys Russian missile defense system after repeated warnings

Ankara's purchase of Russian S-400 air defense system 'renders its continued involvement impossible,' Pentagon says

Decision comes as Ankara continues to ignore warnings from NATO ally over procurement of missile defense system

Key congressional committees express dismay after air defense systems begin arriving in Ankara, say Erdogan chose Putin over NATO

Delivery moves Ankara closer to possible sanctions and new standoff with Washington, which has argued the weapon is incompatible with NATO systems and a threat to its F-35s

Statement comes after Washington threatened to remove Ankara from F-35 fighter jet program and have pilots kicked off training course and expelled from US over purchase from Russia