The US Secretary of State John Kerry has lashed out at Russia for creating unrest in Ukraine by sending agents for this purpose, saying such moves are "absolutely unacceptable".      

"Everything that we've seen in the last 48 hours from Russian provocateurs and agents operating in eastern Ukraine tells us that they've been sent there determined to create chaos. And that is absolutely unacceptable," Kerry told members of the Senate Foreign Relations Committee during a Congressional hearing on Tuesday.  

"These efforts are as ham-handed as they are transparent, frankly. And quite simply what we see from Russia is an illegal and illegitimate effort to destabilise a sovereign state and create a contrived crisis with paid operatives across an international boundary engaged in this initiative," he said.       

Alleging that Russia's clear and unmistakable involvement in destabilising and engaging in separatist activities in the east of Ukraine is more than deeply disturbing, Kerry said no one should be fooled by what "could potentially be a contrived pretext for military intervention" just as the world saw in Crimea, which was previously a province of Ukraine.       

"It is clear that Russian Special Forces and agents have been the catalysts behind the chaos of the last 24 hours. Some have even been arrested and exposed.       

And equally as clear must be the reality that the United States and our allies will not hesitate to use 21st century tools to hold Russia accountable for 19th century behaviour," he said.