Washington (CNN) -- It must have been at least a little satisfying Thursday for President Barack Obama.
He had repeatedly warned Russian President Vladimir Putin against annexing Crimea from Ukraine, threatening tougher sanctions aimed at the Russian economy.
Following the Russian parliament's vote to approve the annexation, Obama made a previously unscheduled appearance before TV cameras to essentially tell Putin: I told you I'd do it.
"These are all choices that the Russian government has made, choices that have been rejected by the international community, as well as the government of Ukraine," Obama said. "And because of these choices, the United States is today moving, as we said we would, to impose additional costs on Russia."
'We said we would'
His hastily arranged remarks signaled European allies that Obama would take a leading role on the issue, and also responded to pressure from political foes and some supporters at home for a tougher response to what Vice President Joe Biden called a "land grab" by Putin.
Even Hillary Clinton, Obama's former secretary of state who is the overwhelming favorite for the Democratic presidential nomination in 2016, said this week that the administration should do more to support Ukraine.
The steps announced Thursday expanded on a previous U.S. list of sanctions targets, adding more senior Russian officials and what officials called "cronies" of Putin as well as a bank controlled by a Putin associate.
Obama also warned Moscow that possible further sanctions would go after key sectors of the economy if Russia escalates the crisis in Ukraine.
A new executive order signed by Obama authorizes his administration to target Russian companies in the financial services, energy, metals and mining, defense and engineering industries -- all vital components of the Russian economy.
EU leaders met Thursday to discuss their own steps, so Obama's immediate response gave him the mantle of leadership on the matter.
Finland's Minister for European Affairs and Foreign Trade Alexander Stubb told CNN's Nina dos Santos that the EU will add as many as 10 more names to its previous list of targets, but won't hit any companies at this stage.
So far, European powers such as Germany and Britain have been unwilling to embrace significant economic sanctions against Russia because of their strong trade and investment ties with Moscow.
In a briefing to reporters, senior U.S. administration officials sounded further warnings against any Russian provocations in Ukraine.
"We believe that it is very important to signal that if Russia further escalates this situation they will be met with severe consequences," one official said.
The tough talk looked even more credible compared to Russia's almost comical response to the U.S. announcement: sanctions against nine U.S. political leaders and administration officials.
Moscow's list included House Speaker John Boehner, Senate Majority Leader Harry Reid, Republican Sens. John McCain and Dan Coats, Democratic Sens. Robert Menendez and Mary Landrieu, and some members of Obama's White House team.
"I guess this means my spring break in Siberia is off, my Gazprom stock is lost, and my secret bank account in Moscow is frozen," McCain joked in response.
'Badge of honor'
Landrieu, who is facing a tough re-election battle this year in generally conservative Louisiana, called her sanction by Russia "a badge of honor."
Obama and U.S. officials have made clear that the response to Russia will remain in the diplomatic and economic arenas, with one senior administration official essentially rejecting for now any direct U.S. effort to bolster Ukraine's military forces for a ground war.
"Nobody wants the outcome here to be a full-bore military conflict between Russia and Ukraine, and in fact, the Ukrainian government themselves have been quite restrained in not giving in to provocation and not having this go the way of bloodshed," the official said, adding that "we don't want to take steps to add to a momentum of further militarizing the situation."
CNNMoney's Mark Thompson and CNN's Dana Bash and Lisa Desjardins contributed to this report.