Intelligence officials in Washington warned European allies of a possible Russian military incursion into Ukraine, as US Secretary of State Anthony Blinken renewed talk of "real" US concern about Moscow's actions and rhetoric on Kiev.
"We have real concerns about Russia's unusual military action on the border with Ukraine. We have real concerns about part of the rhetoric that we've seen and heard from Russia as well as on social media," Blinken told reporters during a visit to Senegal.
The US secretary said that Washington's allies widely share its concerns in this regard, but he refused to clarify whether the US intelligence services believe that Russian President Vladimir Putin aims to extract territory from Ukraine.
"We don't know President Putin's intentions. But we know what happened in the past, we know how to refer to a fictitious provocation from Ukraine or any other country, and to use that as a justification for what Russia was planning to do from the start," he said.
His comments are a reference to the crisis that erupted in 2014 when Russia annexed Crimea and backed separatists fighting a conflict in mostly Russian-speaking eastern Ukraine.
Last Thursday, Putin accused Western countries of escalating the Ukraine conflict by holding military exercises in the Black Sea and sending bombers to fly close to the Russian border.
A ship carrying two American patrol boats crosses the Dardanelles Strait to reinforce the Ukrainian Navy (Reuters)
American support
Meanwhile, US intelligence officials, in statements relayed by Washington officials to CBS, have warned of a possible close Russian incursion into Ukraine.
US intelligence officials believe that Moscow's buildup of tens of thousands of troops on the Ukrainian border may be a preparation for an actual incursion into the Donbass region of eastern Ukraine.
Meanwhile, a ship carrying two US Coast Guard patrol boats, which were re-equipped, crossed the Dardanelles Strait on Saturday to reinforce the Ukrainian navy, after Kiev said it feared Russia was preparing an attack on it.
The ship carrying the two patrol boats left Baltimore on its way to the Ukrainian port of Odessa on November 8.
The US embassy in Kiev says the two boats are part of $2.5 billion in security assistance to Ukraine that began in 2014.