A lawyer for WikiLeaks founder Julian Assange said he won’t voluntarily travel to the U.S. to face charges against him.

The comment follows a revelation that Assange, who is taking asylum in the Ecuadorian Embassy in London, was criminally charged under seal for publicizing confidential government information on his site.

“The burden should not shift to Mr. Assange to have to defend against criminal charges when what he has been accused of doing is what journalists do every day,” Barry Pollack, a Washington lawyer for Assange, said.

“They publish truthful information because the public has a right to know and consider that information and understand what its government and institutions are doing,” he continued, adding that he hopes the Ecuadorian Embassy will continue to “comply with its obligations” and won’t revoke his asylum.

"The burden should not shift to Mr. Assange to have to defend against criminal charges when what he has been accused of doing is what journalists do every day." — Barry Pollack, a Washington lawyer for Julian Assange

Assange first entered the embassy about six years ago in a bid to avoid extradition to Sweden, where he was accused of sex crimes, or to the U.S. for publicizing classified information.

The Ecuadorian government is reportedly getting wary of continuing to offer asylum to Assange amid allegations of espionage, erratic behavior and diplomatic unease.

The charges and arrest warrant were discovered Thursday after prosecutors mistakenly revealed their existence in an unrelated case, writing that the charges “would need to remain sealed until Assange is arrested in connection with the charges in the criminal complaint and can therefore no longer evade or avoid arrest and extradition in this matter.”

The Associated Press separately confirmed the existence of the charges under seal, with a person familiar with the matter saying it remains unclear when the exact charges Assange is facing will be revealed.

But Assange’s refusal to voluntary travel to the U.S. to face charges is likely to prompt a fight for his extradition, as he’s one of the central figures in Special Counsel Robert Mueller’s Russia investigation.

The Department of Justice move to charge indicates the department’s more aggressive stance toward Assange after years of inaction. The charges could also shine a light on whether Russia colluded with the Trump campaign in the 2016 presidential election.

The WikiLeaks founder made his name after publishing thousands of military and State Department cables from Army Pvt. Chelsea Manning, for which Manning served prison time, secret CIA hacking tools, and publicizing email conversations from top Democratic Party officials.

The Associated Press contributed to this report.