The United States is preparing fresh sanctions against Russia over the near-fatal poisoning of Kremlin critic Alexei Navalny, a top White House advisor warned Sunday.
Jailed opposition leader Navalny, President Vladimir Putin's most prominent opponent, was arrested in January upon returning to Russia after recovering from a poisoning he says was orchestrated by Moscow.
Diplomatic relations between Moscow and Washington have soured since President Joe Biden took office in January.
Biden's national security advisor Jake Sullivan noted Sunday that the US has already sanctioned Russia for "the poisoning of Alexei Navalny."
"We rallied European allies in a joint effort to impose costs on Russia for the use of a ทดลองเล่นสล็อต chemical agent against one of their citizens on Russian soil," he told CNN's "State of the Union."
But he said "We are preparing another package of sanctions to apply in this case ... We've shown along the way we're not going to pull our punches."
- 'Illegal actions' -
Moscow pushed back against the possibility of new sanctions and warned of a Russian response.
"The illegal actions of the United States have always been followed by a legitimate response from us," Foreign Ministry spokeswoman Maria Zakharova said on Telegram.
And Anatoly Antonov, the Russian ambassador to the US, said that "this was not the signal that everyone received after the summit" in Geneva last week between Biden and Russian President Vladimir Putin.
Among other things, the two leaders agreed to return their respective ambassadors -- the Russian Antonov and the American John Sullivan, withdrawn in tit-for-tat fashion after Biden in March likened Putin to a "killer."
Speaking Sunday upon his arrival back in New York, Antonov said he had just learned of the sanctions threat.
"I think that it is not possible to stabilise relations, improve mutual relations between two countries, through sanctions," he said, calling instead for a restoration of dialogue.
Biden and Putin sought in Geneva to cool tensions in the combustible US-Russian relationship.
Putin has rejected criticism of his treatment of opponents -- many high-profile critics have been killed in Russia during his rule and the media is almost entirely muzzled -- saying that the United States had bigger problems.
A day after the summit, the Kremlin was guarded about future dialogue with Washington.
"We are ready to continue this dialogue to the same extent as the American side is," Putin said in televised remarks.
The Russian leader said the meeting was "quite friendly" and that he and Biden "were able to understand each other on key issues."