President Vladimir Putin says Russia will be forced to retaliate at some point if Washington presses ahead with new sanctions against Moscow, but says his response will depend on the final text of the proposed law.
Russia was speaking after the US House of Representatives overwhelmingly voted to impose new sanctions on Moscow and to force President Donald Trump to obtain lawmakers' permission before easing any sanctions on Russia.
Mr Putin, on a visit to Finland, said on Thursday the proposed US sanctions were "extremely cynical" and an attempt by Washington to safeguard its own geopolitical interests at the expense of its allies in Europe.
Investigations into Russia's alleged meddling in the US Presidential elections were merely a symptom of growing anti-Russian hysteria in the United States, Mr Putin said.
But Mr Trump could still veto the pending legislation, White House Communications Director Anthony Scaramucci told CNN on Thursday.
"He may sign the sanctions exactly the way they are or he may veto the sanctions and negotiate an even tougher deal against the Russians."
Russia had earlier warned it could retaliate, while the European Union said the US move might affect its energy security and prompt it to act, too.
The US House of Representatives has already approved the sanctions. If the bill passes the Senate as expected, it would be sent to the White House for Trump to sign into law or veto.
If Mr Trump vetoes it, however, the measure is expected to garner enough bipartisan support to override it.
Mr Scaramucci, who was appointed on Friday, cast the President's consideration of a possible veto in light of his core supporters in an interview on CNN's New Day program.
"He is a counterintuitive, counterpunching personality," citing the President's recent "fan base" at a recent rally.
"The American people get it. The American people like what he is doing. The establishment does not like what he is doing. He's going to disrupt the establishment."