Russian President Vladimir Putin lambasted the U.S. judicial system, saying it was being used by former U.S. leader Donald Trump’s political enemies to pursue the Republican presidential nominee.

“They [the U.S.] are burning themselves from the inside, their state, their political system,” Putin told media editors at the St Petersburg International Economic Forum on Wednesday.

“It is obvious all over the world that the prosecution of Trump, especially in court on charges that were formed on the basis of events that happened years ago, without direct proof, is simply using the judicial system in an internal political struggle,” he said, in comments translated by Reuters.

CNBC has reached out to the U.S. Department of Justice for comment.

A New York jury in late May found Trump guilty of falsifying business records in an effort to conceal a hush money payment to a pornography star ahead of the 2016 presidential election. Trump denied all the charges and slammed the court proceedings as a “rigged, disgraceful trial.” He is expected to appeal the historic verdict after he is sentenced on July 11, but legal experts say there is no chance he will overturn his conviction prior to the Nov. 5 election.

Asked on Wednesday whether he would prefer Trump or incumbent Joe Biden to win the vote, Putin said that “it doesn’t matter” to Moscow who becomes the next U.S. leader. Either way, he said, it was unlikely that U.S. foreign policy toward Russia would change.

“Basically, we don’t care [who wins],” Putin said. “For us, we do not think the end result holds much significance. We will work with any president the American people elect.”

He added, “To say — I am speaking quite sincerely — that we believe that after the elections something will change towards Russia in American policy, I would not say so. We don’t think so. We think that nothing really serious will happen.”

Back in February, Putin said he preferred Biden to be the next U.S. president, describing him as a more experienced and more predictable” politician.

On Wednesday, he told journalists that Biden was “an old-school politician” while playing down his support for Trump’s campaign.

“We have never had any special ties with Mr Trump, but the fact remains that as president he started imposing massive sanctions on Russia, he withdrew from the treaty on intermediate and shorter-range missiles,” Putin said.