The United States on Thursday announced a set of punitive measures against individuals and entities endangering Ukraine's sovereignty and integrity.
Some of those responsible — Russian and Ukrainian officials — had their US visas withdrawn, if they had them, with immediate effect. Others, who apply, will be turned down.
The US will also be designating individuals and entities for targeted sanctions going forward.
As of this morning, whoever threatened Ukraine's peace, security, stability, sovereignty, or territorial integrity "was on notice", said a senior administration official.
The US doesn't identify people it denies visa, but it will name those it designates for targeted sanctions, going forward. No one is on that list yet, said an official.
The US has already been denying visas to those "involved in human rights abuses related to political oppression in Ukraine". That list will now swell to cover more people.
President Barack Obama had threatened Russia with costs of intervening militarily in Ukraine and it has set into motion a set of actions over past days to inflict them.
The US has put on hold preparatory meetings for the Sochi G-8 meet, cancelled bilateral talks with Russia, and beefed up its NATO commitments in the Baltic region.
The measures announced on Thursday were intended to "send a strong signal that we intend to impose costs on Russia", said an official, adding the US was prepared for retaliatory action.
US lawmakers, meanwhile, continued to step up pressure on the administration for imposing sanctions on Russia, with support from both sides of the aisle.