Russia's Foreign Ministry said on Saturday Moscow would retaliate against the United States' most recent sanctions over Ukraine by denying entry to several U.S. citizens.
"Retaliatory measures definitely will be taken. First of all, a similar number of Americans will be prohibited from entering (Russia)," the ministry's spokesman Alexander Lukashevich was quoted in a statement as saying.
Lukashevich did not give names of those who would be denied entry.
This week U.S. President Barack Obama imposed sanctions on some of Russia's biggest firms for the first time, as well as four Russian government officials and prime minister of the self-styled Donetsk People's Republic in Ukraine.