Chinese experts warned that the United States military is "walking on thin ice" by allowing one of its U-2 spy planes to trespass into a no-fly zone over Chinese live-fire military drills, calling the move extremely provocative and prone to misjudgement.

The Chinese military strongly protests a high-altitude US spy plane trespassing into the no-fly zone that is currently hosting a live ammunition drill by the People's Liberation Army Northern Theater Command, Senior Colonel Wu Qian, spokesman for the Ministry of National Defense, said in a statement on Tuesday.