The sanctions come after Sunday’s referendum in Crimea, regarded as illegal by Brussels, Washington and Kiev, in which officials say 97% of voters endorsed breaking away from Ukraine and joining Russia.
The EU has agreed to impose travel bans and asset freezes against 21 officials from Russia and Ukraine, according to BBC reports.
While the 21 people have not yet been named, the list is understood to focus on individuals seen as having played a key role in the referendum.
The EU announced the sanctions after a meeting of foreign ministers in Brussels.
Lithuania’s Foreign Minister Linas Linkevic tweeted that further measures were expected to be taken in the next few days.
The US has also imposed sanctions on 11 individuals.
Washington said it had targeted seven top Russian government officials and four Crimea-based separatist leaders with financial sanctions for undermining “democratic processes and institutions in Ukraine”.
The officials include acting Crimean leader Sergei Aksyonov, Russian deputy prime minister Dmitry Rogozin, and Russian upper house leader Valentina Matviyenko.
Speaking earlier to Austrian radio station ORF, Vienna’s foreign minister Sebastian Kurz denied that Gazprom chief executive Alexei Miller and Rosneft president Igor Sechin would face a visa ban and asset freeze.
“This is not expected at this time,” Kurz said when asked about the two men, who had been reported by Germany’s Bild newspaper as well as other news organisations as being on the earlier draft list of between 120 and 130 names.
“I think picking business bosses indiscriminately would be a wrong step,” the minister said in an interview cited by Reuters.
Analysts said they believed Gazprom’s importance as a gas supplier to Europe meant it was unlikely to be a target of the sanctions.
“Falling European production, coupled with the Asia-Pacific market swallowing up LNG volumes … means that Europe does not have much flexibility in terms of cutting gas purchases from Russia, implying that Gazprom is most likely not vulnerable to possible EU economic sanctions,” Alfa bank said in a note.