Russian Foreign Minister Sergei Lavrov has told US Secretary of State Mike Pompeo by phone that further "aggressive steps" in Venezuela would be fraught with the gravest consequences, Russia's Foreign Ministry says.
Lavrov also condemned what he called the US' "interference" in Venezuela's internal affairs as a breach of international law, adding that dialogue between all political forces is required in the Latin American country.
The White House National Security Council scheduled a meeting for Wednesday afternoon to discuss next steps on Venezuela, and acting Defence Secretary Patrick Shanahan cancelled a trip to Europe because of Venezuela.
Pompeo earlier said US military action in Venezuela is possible, but Washington prefers a peaceful transition.
"Military action is possible. If that's what's required, that's what the United States will do. We're trying to do everything we can to avoid violence," Pompeo told the Fox Business Network on Wednesday.
The Pentagon downplayed any active planning to directly intervene in Venezuela, telling Congress it had not been given orders to prepare for war and stressing support for diplomacy.
Pompeo said on Tuesday that Maduro was prepared to leave the country but nixed his plan after Russia intervened. A spokeswoman for Russia's foreign ministry denied that.
White House national security adviser John Bolton, a Trump administration hawk on Venezuela, made clear that Moscow's interference was not welcome.
"This is our hemisphere," he told reporters outside the White House. "It's not where the Russians ought to be interfering. This is a mistake on their part. It's not going to lead to an improvement of relations."
Bolton expressed confidence the opposition in Venezuela will manage to peacefully secure the ouster of President Nicolas Maduro.
"We are going to see that peaceful transition of power," Bolton said in an interview with Fox News.
"The overwhelming number of military service members in Venezuela support Juan Guaido and the opposition," Bolton said, referring to the self-declared interim President. "It's just a matter of time until they come over to the opposition," Bolton asserted.
Asked if Venezuela could become another Syria-like conflict situation, Bolton said: "We won't let it get to that point."
Meanwhile acting US defence secretary Patrick Shanahan has cancelled plans to travel to Europe, citing the crisis in Venezuela and the situation along the US-Mexico border.
A Shanahan spokesman, Lieutenant Colonel Joe Buccino, said in a statement Shanahan decided he should remain in Washington to co-ordinate with the National Security Council and the State Department on Venezuela and the border, where the military is assisting the Homeland Security Department with the migrant crisis.