Edward Snowden, the former contractor for the National Security Agency who in 2013 leaked classified information that showed the U.S. government surveilled private data, said in an interview published over the weekend that retired Gen. David Petraeus "shared information that was far more highly classified than I ever did with journalists."

Petraeus, who is the former director of the CIA, has emerged as one of President-elect Donald Trump's potential picks for secretary of state.

"We have a two-tiered system of justice in the United States, where people who are either well-connected to government or have access to an incredible amount of resources get very light punishments," Snowden told Yahoo News' Katie Couric.

"Perhaps the best-known case in recent history here is Gen. Petraeus, who shared information that was far more highly classified than I ever did with journalists," he added.

.@Snowden says Trump's possible SoS pick David Petraeus disclosed info "far more highly classified than I ever did." pic.twitter.com/QNqx9tr7cf

— Kyle Griffin (@kylegriffin1) December 4, 2016

In 2015, Petraeus pled guilty to a misdemeanor charge of mishandling classified information after he disclosed government secrets to his biographer Paula Broadwell, with whom he was having an affair. According to court documents, the general handed Broadwell a black book of "code word" documents, which were highly classified and included identification of covert agents and notes about National Security Council meetings. Petraeus retrieved the information three days later and none of it was ever publicized.

Petraeus was sentenced to two years of probation and ordered to pay $100,000 in fines. However, several former U.S. intelligence officials disagreed with Snowden's assertion that Petraeus shared "far more highly classified" information than he. Tommy Vietor, who served as a national security spokesman in President Barack Obama's administration, pushed back against the former NSA contractor's comments.

But Snowden, who lives in Moscow, Russia, took to Twitter Sunday to argue that his claim during his sit-down with Couric "was established by the FBI."

Snowden, who says he leaked the classified information to expose the NSA's practices and inform the American public, told Couric the only reason Petraeus shared private data was for his own personal benefit. He later followed up with a tweet, writing, "His desire to sleep with his biographer was greater than his concern for agents’ safety."

"[Petraeus] shared this information not with the public for their benefit, but with his biographer and lover for personal benefit — conversations that had information, detailed information, about military special-access programs, that’s classified above top secret, conversations with the president and so on," Snowden said, adding that the general "never spent a single day in jail, despite the type of classified information he exposed."

Though Petraeus hasn't acknowledged Snowden's assertions specifically, he did apologize once again for his mistakes during an interview Sunday on ABC's "This Week."

"What I would say to [nervous Republicans] is what I've acknowledged for a number of years, that five years ago I made a serious mistake. I acknowledged it. I apologized for it. I paid a very heavy price for it, and I've learned from it," he told host George Stephanopoulos.

Having been charged with treason, Snowden has been working to get Obama to pardon him before President-elect Donald Trump assumes the White House in January. Trump's nominee for CIA director, Rep. Mike Pompeo (R-Kan.), has called for "traitor Edward Snowden" to be "given the death sentence."