President Barack Obama is imposing sanctions against Russian officials after Crimea's vote to secede from Ukraine.
Obama's executive order issued Monday names seven Russian government officials. The United States also says it identifies and targets the assets of other individuals who aren't government officials but are supporting them.
The Treasury Department also is imposing sanctions on four Ukrainians, including former President Viktor Yanukovych and two Crimea-based separatist leaders.
The U.S. announcement came shortly after the European Union announced travel bans and asset freezes on 21 people.
The sanctions were expected after residents in Crimea voted overwhelmingly Sunday in favor of the split.
Meanwhile, European Union foreign ministers have slapped travel bans and asset freezes on 21 people they have linked to the push for the secession and possible annexation of Ukraine's Crimean peninsula.
The sanctions came hours after Crimea's parliament declared the region an independent state, following its residents' overwhelming vote to break away from Ukraine and seek to join Russia.
The ministers meeting in Brussels did not immediately release the names and nationalities of those facing 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.