European foreign ministers and US president Barack Obama have agreed to impose economic and diplomatic sanctions against officials from Crimea and Russia.
Lithuanian foreign minister Linas Linkevičius reported that 21 Russian and Ukrainian political and military officials, deemed responsible for a contended independence referendum in Crimea would be targeted by sanctions including travel bans and asset freezes.
The White House announced with an executive order the freezing of assets of seven Russian officials involved in the Crimea incursion.
The government officials include: state Duma deputies Yelena Mizulina - also author of the anti-gay propaganda bill - and Leonid Slutsky; Andrei Klishas, chairman of the Russian federation council committee on constituional law, judicial and legal affairs; Federation Council Speaker Valentina Ivanovna Matviyenko; presidential advisor for the President Sergei Glaziev; Vladislav Surkov, top aide to the Kremlin; and Dmitry Rogozin, deputy prime minister and former Russian ambassador to Nato.
The Treasury Department also is imposing sanctions on four Ukrainians, including former President Viktor Yanukovich and two Crimea-based separatist leaders.
The EU ministers meeting in Brussels did not immediately release the names of those targeted by the sanctions.
Last week, Germany's Bild tabloid reported that the list would include 13 Russian politicians close to President Vladimir Putin, such as Defence minister Sergei Shoigu, Rogozin, head of presidential administration Sergei Ivanov, secretary of the National Security Council Nikolai Patrushev.
Visa bans would also target Alexei Miller chief executive of Russian energy firm Gazprom, and Igor Sechin, head of Russia's top crude oil producer Rosneft.
More measures will come in the following days, according to Linkevičius.
The EU measures will likely have a greater impact on Russia than the American ones, considering that the continent's €335bn (£280bn, $467bn) of trade with Russia in 2012 is worth about 10 times that of the US.
Europe buys most of Russia's oil and gas exports, with Germany, Italy and France being the top importers. Russian government officials and businessmen are getting ready for Iran-like sanctions, according to a Bloomberg report.
Crimea parliament formally voted to declare independence from Ukraine following an overwhelming outcome from the referendum to secede from Kiev rule and join Russia.
A formal application to join Russia was sent after 93% of Crimea residents reportedly voted in favour of the split, in a referendum that the US and the EU say violates the Ukrainian constitution and international law.
US president Barack Obama told Russian president Vladimir Putin that the Crimean vote occurred "under duress of Russian military intervention" and would not be recognised.