BERLIN (AFP) - Germany welcomes "clear language" from the United States on Russia, Foreign Minister Heiko Maas said on Thursday (March 18), after President Joe Biden branded his Russian counterpart a "killer".

"Since the Biden administration took office, the conversations that we have had with different representatives have made clear that there will be clear language in Washington on Russia. And Joe Biden has in particular proven this," said Maas.

"In this respect, we assume that the policy from Washington will be very outspoken on the things on which we have different opinions," Maas said, adding that he still hoped for dialogue and agreement on "major global challenges".

In an interview with ABC News on Wednesday, Biden said Russian President Vladimir Putin would "pay a price" for trying to undermine his candidacy in the US election in 2020.

Asked if he thought Putin was "a killer", Biden replied: "I do."

His comments stood in stark contrast with his predecessor, Donald Trump, who was often accused of going soft on Putin.

Biden's comments sparked the biggest crisis between Russia and the United States in years, with Moscow recalling its ambassador for consultations and warning that ties were on the brink of outright "collapse".

Putin on Thursday mocked Biden for calling him a "killer" - saying "it takes one to know one".