The United States is changing its language to reflect the depth of Russian involvement in the conflict in eastern Ukraine.
The Associated Press reported on April 30 that U.S. officials briefed on intelligence from the region say Russia has significantly deepened its command and control of separatist forces in recent months.
That has led the United States to quietly introduce a new term "combined Russian-separatist forces."
The State Department used the expression three times in a single statement last week, lambasting Moscow and the rebels for a series of cease-fire violations.
AP says U.S. intelligence agencies signed off on the new language last week, after what officials described as increasing evidence of the Russians and separatists working together, training together, and operating under a joint command structure that ultimately answers to Russia.
The shift in U.S. perceptions could have wide-ranging ramifications, including making it harder for Russia to persuade the United States and Europe to scale back sanctions that are hurting its economy, and for Washington and Moscow to cooperate on matters from nuclear nonproliferation to counterterrorism.