Russia has some 100,000 troops near Ukraine, though it denies planning to invade.
Responding to US President Joe Biden’s decision to deploy extra troops to Europe this week, Russian Deputy Foreign Minister Alexander Grushko said it was a “destructive” and an “unjustified” step. He said the decision has heightened tension and reduced the possibility of a political solution.
The Russia-Ukraine tensions come eight years after Russia annexed Ukraine’s southern Crimea peninsula and backed a bloody rebellion in the eastern Donbas region and at least 14,000 people have been killed since 2014.
Speaking on Wednesday, Grushko added that it would “delight” the Ukrainian authorities.
The Pentagon earlier said the American troops being deployed would not fight in Ukraine but would ensure the defence of Washington’s allies.
Their deployment is in addition to the 8,500 troops the Pentagon put on alert last month to be ready to deploy to Europe if needed.
“It’s important that we send a strong signal to Mr Putin and, frankly, to the world that Nato matters to the United States and it matters to our allies,” Pentagon spokesman John Kirby told reporters on Wednesday.
But on the question of alleged invasion plans by Mr Putin, he said: “We still don’t believe he’s made a decision to further invade Ukraine.”