Tensions between Washington and Moscow over Venezuela continue to rise.
Russia on March 30 dismissed U.S. concerns about "specialists" it has sent to Venezuela under a military cooperation deal.
"The Russian side clearly stated the purpose of the arrival of its specialists to Caracas. This is not about any 'military contingents'," Russian Foreign Ministry spokeswoman Maria Zakharova said in a statement.
Her comments came a day after U.S. national-security adviser John Bolton warned "actors external to the Western Hemisphere against deploying military assets to Venezuela."
Two Russian military planes landed in Venezuela a week ago and offloaded troops and equipment, ratcheting up international tensions amid a standoff between Venezuela's government and the opposition.
U.S. President Donald Trump has called on Russia to "get out" of Venezuela, with Russia saying its troops will stay as long as needed.
Earlier on March 30, Rosoboroneksport, Russia's state arms exporter, said it had opened a training center for military helicopter pilots in Venezuela.
Venezuela, Russia's largest client in Latin America, has already received "a significant amount of Russian arms and military technology," Rosoboroneksport added.
The United States and more than 50 other countries recognize Venezuelan opposition leader Juan Guaido as interim president. Russia, along with China, backs President Nicolas Maduro.