WASHINGTON, 01 December 2021, (TON): United States warned Russia of "serious consequences" if it launches an invasion of Ukraine, as Nato ministers looked to counter a military build-up by Moscow on its neighbour's border.

The long-scheduled meeting of NATO top diplomats in Latvia's capital Riga comes at a volatile moment along the bloc's eastern flank as allies also grapple with a migrant crisis the West says is fuelled by Kremlin-backed Belarus.

Western countries spearheaded by the United States worry that Moscow could be planning an incursion into Ukraine after accusing the Kremlin of massing tens of thousands of troops and heavy armour close to the frontier.

US Secretary of State Antony Blinken told journalists ahead of the meeting that any escalatory actions by Russia would be of great concern to the United States...and any renewed aggression would trigger serious consequences."

"We have seen Russia's playbook many times over."

Moscow, which seized Crimea from Ukraine in 2014 and backs separatists fighting Kiev, has strongly denied it is plotting an attack and blames Nato for fuelling tensions.