The U.S. government on Thursday sanctioned four Ukrainian officials it accuses of being involved in activities backed by the Russian government to destabilize Ukraine.
It comes amid the United States warning of further action if Russia invades Ukraine. Russia has massed some 100,000 troops on its borders with Ukraine, but denies it is planning an attack. Russian officials are demanding written guarantees that NATO will give up any military activity in Eastern Europe and Ukraine, but members of the alliance have refused to issue such promises.
