Russia's interior ministry has put US Senator Lindsey Graham on a wanted list, Russian media reported on Monday, citing the ministry's database.
Graham disputed Russian criticism of his support for Ukraine on Sunday, saying he had simply praised the spirit of Ukrainians in resisting a Russian invasion with assistance provided by Washington.
Russia on Sunday condemned Senator Graham for telling Ukrainian President Volodymyr Zelensky during a visit to Kyiv that US support for Ukraine was the best money Washington had ever spent and that "the Russians are dying."
At a meeting on Friday, Zelensky told Graham that "now we are free."
"And the Russians are dying," Graham said, according to a video supplied by the Ukrainian presidential press service.
In the next part of the video edit, Graham says with a smile: "It's the best money we've ever spent."
The exact chronology of Graham's remarks was unclear from the video supplied by the Ukrainian presidential press service.
The Ukrainian president's office did not immediately reply on Sunday to a request for a full transcript of Graham's remarks at the meeting.
Russia condemnation of Graham's comments.
"It is difficult to imagine a greater shame for a country than having such senators," Kremlin spokesman Dmitry Peskov was quoted as saying by the Shot Telegram channel.
Russian Security Council Deputy Chairman Dmitry Medvedev called Graham, a 67-year-old Republican, an old fool.
"The old fool Senator Lindsey Graham said that the United States has never spent money so successfully as on the murder of Russians," said Russian Security Council Deputy Chairman Dmitry Medvedev. "He shouldn't have done that."
As usual the Russia propaganda machine is hard at work," Graham told Reuters in an emailed statement on Sunday, referring to Medvedev's comments about his Kyiv visit, which he had used to urge Washington to send more weapons to Ukraine.
Graham said he had mentioned to Zelensky "that Ukraine has adopted the American mantra, 'Live Free or Die.' It has been a good investment by the United States to help liberate Ukraine from Russian war criminals."
He added, "Mr. Medvedev, if you want Russians to stop dying in Ukraine, withdraw. Stop the invasion. Stop the war crimes. The truth is that you and (President Vladimir) Putin could care less about Russian soldiers," he said.
Ukrainian presidential adviser, Mykhailo Podolyak, said in Twitter comments on Sunday that the best investment the United States and the West could make was "in a complete and unconditional victory of Ukraine."