MOSCOW: Movement to and from the border is meant to make any tactical moves murky and cause uncertainty

Russia is orchestrating a multi-front offensive involving up to 175,000 troops as soon as next year, US media reported, as Ukraine warned that a large-scale attack may be planned for next month.

Moscow's plans "involve extensive movement of 100 battalion tactical groups with an estimated 175,000 personnel, along with armor, artillery and equipment," a US administration official told media on condition of anonymity.

While the Pentagon told media it would not comment on intelligence matters, it said it was "deeply concerned by evidence that Russia has made plans for aggressive actions against Ukraine."

Pentagon spokesman Lieutenant Colonel Tony Semelroth said "we continue to support de-escalation in the region and a diplomatic resolution to the conflict in eastern Ukraine.”

Russian forces are currently massing at four points, with 50 battlefield tactical groups deployed in addition to the fresh arrival of tanks and artillery, the Post said, citing an unclassified US intelligence document.