Russia was motivated to agree to Thursday's massive prisoner swap with the United States out of fear of former President Donald Trump returning to office, according to his running mate, Sen. J.D. Vance.

"We certainly want these Americans to come back home. It was ridiculous that they were in prison to begin with," the Ohio Republican told CNN, adding that the exchange, which included the release of Wall Street journalist Evan Gershkovich and retired U.S. Marine Paul Whelan, was "great news."

But, he said, "we have to ask ourselves: Why are they coming home?"

"I think it's because bad guys all over the world recognize Donald Trump's about to be back in office, so they're cleaning house," Vance said. "That's a good thing, and I think it's a testament to Donald Trump's strength."

The prisoner swap involved seven countries, marking the largest exchange between Russia and the United States since the Cold War ended.

And while Vance was giving credit for the exchange to Trump, the former president and GOP presidential nominee was slamming it on social media and asking if it involved a cash transfer.

"Are we releasing murderers, killers, or thugs?" Trump said on Truth Social. "Just curious because we never make good deals, at anything, but especially hostage swaps…they're calling the trade 'complex' – That's so nobody can figure out how bad it is!"

National Security Adviser Jake Sullivan, when asked during Thursday's White House briefing about Vance's claims, simply commented "I don't follow" before moving on to other questions, reports The Hill.

Sullivan also said that no money or sanctions relief was given to Russia.

According to the Turkish presidential office, which helped in the exchange, more than two dozen prisoners were released from the United States, Germany, Poland, Belarus, Norway, Russia, and Slovenia in the exchange.

Meanwhile, a reporter asked President Joe Biden, who announced the exchange Thursday, about Trump's claims that he would have gotten hostages released without giving anything in exchange.

He replied: "Why didn't he do it when he was president?"

• Source: Harris Back to D.C. to Greet Prisoners Freed in Swap
• Kremlin: 'Let Our Enemies Who Have Left Russia Stay Away'