The foreign minister, referencing Russia's 2008 conflict with Georgia, was quoted as saying:
"If our interests, our legitimate interests, the interests of Russians have been attacked directly, like they were in South Ossetia for example, I do not see any other way but to respond in accordance with international law."
In 2008, Russia engaged in two days of armed conflict in South Ossetia, claiming it was acting to protect the interests of ethnic Russians. Since that conflict, Russia is only one of four countries that recognizes South Ossetia as independent from Georgia.
"Russian citizens being attacked is an attack against the Russian federation," Lavrov said Wednesday.
Russia Today tweeted Lavrov's warning: "If we are attacked, we will certainly respond."
The foreign minister did not specify what response Russia would take.
The interview follows U.S. Vice President Joe Biden's visit to Kiev on Monday and Tuesday for consultations with Ukrainian government officials and civil society leaders, as well as the U.S. government decision to conduct military exercises in Eastern Europe.
Regarding Biden's visit, Lavrov commented, "There is no reason not to believe that the Americans are running the show."