President Obama reaffirmed Monday that Crimea's vote in favor of joining Russia will not be recognized by the international community, as his administration -- and the European Union -- sanctioned top Russian officials over Sunday's referendum.
"We're making it clear that there are consequences for their actions," Obama said in the White House briefing room.
The president spoke just hours after Crimea's parliament declared the region an independent state, following its residents' overwhelming vote Sunday to break away from Ukraine and seek to join Russia.

The president said he believes "there's still a path to resolve this situation diplomatically" but announced expanded sanctions to "increase the costs" on those responsible for the stand-off.

While stopping short of singling out Russian President Vladimir Putin himself, Obama sanctioned several members of Putin's inner circle. The administration also announced sanctions against separatist leaders in Crimea and former president of Ukraine Viktor Yanukovych.

"We have fashioned these sanctions to impose costs on named individuals who wield influence in the Russian government and those responsible for the deteriorating situation in Ukraine," the White House said in a statement. "We stand ready to use these authorities in a direct and targeted fashion as events warrant."

The expanded U.S. sanctions, announced in an executive order, would target the assets of the listed Russian officials and bar them from entering the U.S. These include Putin aides Vladislav Surkov and Sergey Glazyev.

It's unclear what other steps the U.S. might take in the coming days, as Western leaders try to prevent Moscow from attempting to formally annex Crimea. Obama told Putin on Sunday that the vote "would never be recognized" by the United States, as he and other top U.S. officials warned Moscow against making further military moves toward southern and eastern Ukraine.

Meanwhile, European Union foreign ministers slapped travel bans and asset freezes Monday on 21 people from Russia and Crimea who they linked to the push for the secession of Ukraine's strategic Black Sea peninsula.

The sanctions came hours after Crimea's parliament declared the region an independent state, following its residents' overwhelming vote Sunday to break away from Ukraine and seek to join Russia.

The ministers meeting in Brussels did not immediately release the names of those targeted by the sanctions.

Two diplomats said the sanctions targeted 13 Russians and eight people from Crimea. The diplomats spoke on condition of anonymity because the breakdown of the nationalities had not been officially announced.

The 28-nation EU and the United States say Sunday's Crimean referendum was illegitimate and unconstitutional.

The EU is walking a tightrope between punishing Moscow and keeping open lines of communication with Russia for a diplomatic resolution of one of the worst geopolitical crises in years on its eastern doorstep.

Before Monday's meeting in Brussels, German Foreign Minister Frank-Walter Steinmeier said sanctions must leave "ways and possibilities open to prevent a further escalation that could lead to the division of Europe."

The EU has already suspended talks with Russia on a wide-ranging economic pact and a visa agreement. The bloc's leaders are meeting Thursday and Friday and could start slapping economic sanctions on Russia this weekend if Moscow does not back down.

Western allies are calling on Putin to "de-escalate" the crisis, support Ukrainian plans for political reform, return Russian troops in Crimea to their barracks and halt advances into Ukraine and military buildups along its borders.

Ukraine's new government in Kiev called Sunday's referendum a "circus" directed at gunpoint by Moscow. Putin, however, insisted it was conducted in "full accordance with international law and the U.N. charter" and cited Kosovo's independence from Serbia as its precedent.