US prosecutors unsealed a 37-count indictment against Donald Trump on Friday, accusing the former president of risking some of the country's most sensitive security secrets after leaving the White House in 2021.

Trump mishandled classified documents that included information about the secretive US nuclear programme and potential domestic vulnerabilities in the event of an attack, the federal indictment said.

Trump also discussed with his lawyers the possibility of lying to government officials seeking to recover the documents; stored some documents in boxes around a toilet, and moved others around his Mar-a-Lago resort home in Florida to prevent them from being found, the charges said.

"Wouldn't it be better if we just told them we don't have anything here?" Trump said to one of his attorneys, according to the 49-page indictment.

Unauthorized disclosure of classified documents posed a risk to U.S. national security, foreign relations, and intelligence gathering, prosecutors said.

The Justice Department made the criminal charges public on a tumultuous day in which two of Trump's lawyers, John Rowley and Jim Trusty, quit the case for reasons that were not immediately clear. A former aide, Walt Nauta, faces charges of being Trump's co-conspirator.

Trump is due to make a first appearance in the case in a Miami court on Tuesday, a day before his 77th birthday.

Since Trump would serve any sentences concurrently if convicted, the maximum prison time he would face is 20 years for obstruction of justice, a charge carrying the highest penalty.

"Our laws that protect national defense information are critical to the safety and security of the United States, and they must be enforced," U.S. Special Counsel Jack Smith, who is leading the prosecution, said at a press conference.

"We have one set of laws in this country, and they apply to everybody," Smith said in his first public appearance since Attorney General Merrick Garland assigned him to the investigation last year.

Smith said he would seek a speedy jury trial in Florida.

Trump has proclaimed his innocence. After the charges were unsealed, he attacked Smith on social media.

"He is a Trump Hater - a deranged 'psycho' that shouldn't be involved in any case having to do with 'Justice,'" Trump wrote on his Truth Social platform.

The indictment of a former U.S. president on federal charges is unprecedented in American history and emerges at a time when Trump is the front-runner for the Republican presidential nomination next year.

Trump's legal woes have yet to dent his popularity with Republican voters, according to Reuters/Ipsos polling.

But the charges laid out against him on Friday could give his Republican rivals in the presidential race ammunition to attack his national-security credentials. So far, they have largely sided with him.

"It’s impossible to bet against Trump’s staying power with the Republican base," said Matt Bennett of the center-left think tank Third Way. "But this conduct charged in this indictment is even worse than we expected - that might break through."

Trump and his allies have portrayed the case as political retaliation by Democratic President Joe Biden, but Biden has kept his distance.

The White House said Biden had no advance knowledge of the indictment, and he later declined to comment when reporters asked about it.

Trump kept the documents at Mar-a-Lago and his golf club in New Jersey. Mar-a-Lago hosted tens of thousands of guests at more than 150 events during the time they were there, the indictment alleges, and it includes photos of Trump’s boxes on a ballroom stage, in a club bathroom and in a storage room, where some lay on the floor.

The classified materials came from seven federal intelligence agencies, including the Pentagon, the CIA, the National Security Agency and the Department of Energy, the indictment said. One document concerned a foreign country's support of terrorism against U.S. interests.

Prosecutors said Trump showed someone a Defense Department document described as a "plan of attack" against another country.

The indictment also alleges Trump conspired with Nauta to keep classified documents Trump had taken from the White House and hide them from a federal grand jury. Nauta, who worked for Trump at the White House and at Mar-a-Lago, faces six counts in the case.

Nauta falsely told the FBI he did not know how some of the documents ended up in Trump's suite at Mar-a-Lago, when in fact he had been involved in moving them there from a storage room, according to the indictment.

An attorney for Nauta declined to comment.

Investigators seized roughly 13,000 documents at Mar-a-Lago nearly a year ago. One hundred were marked as classified, even though one of Trump's lawyers had previously said all records with classified markings had been returned to the government.

Trump has previously said he declassified those documents while president, but the indictment alleges he had acknowledged that he lost that power when he left office.

U.S. District Judge Aileen Cannon has been initially assigned to oversee the case, a source who was briefed on the matter said on Friday. She could preside over the trial as well, said the source, who spoke on condition of anonymity.

Cannon, appointed by Trump in 2019, made headlines last year when she decided in favor of the former U.S. president at a pivotal stage of the case and was later reversed on appeal.

It is the second criminal case for Trump, who is due to go on trial in New York next March in a state case stemming from a hush-money payment to a porn star.

If he wins the presidency again, Trump could potentially try to pardon himself, a legal move that would be controversial and unprecedented.

He would not, however, have any power to derail the state case against him.

The case does not prevent Trump from campaigning or taking office if he were to win the November 2024 presidential election. Legal experts say there would be no basis to block his swearing-in even if he were convicted and sent to prison.

Special Counsel Smith is leading a second criminal probe into efforts by Trump and his allies to overturn his 2020 election loss to Biden, a Democrat.

Trump faces a separate criminal probe in Georgia related to efforts to overturn his loss to Biden in that state.