Trusty also confirmed Trump would show up in court and “is not shrinking from the fight”. But there would be “no arrests, no warrant, none of that kind of nonsense,” he told CNN.

Smith is also investigating Trump’s role in the Capitol attack on January 6, 2021, in which he attempted to stop the certification of President Joe Biden’s election victory.

And in yet another legal woe that is expected to come to a head shortly, Trump is also under investigation in Georgia for attempting to influence the 2020 Electoral College outcome in that state.

Last month, a civil jury also found Trump had sexually abused and defamed New York author E. Jean Carroll, and awarded her $US5 million ($7.4 million) in damages.

Trump has repeatedly characterised every investigation as a “politically motivated witch-hunt” and “election interference at the highest level”.

Loading

And in a sign that many Republicans agree, he continues to be the overwhelming frontrunner to win the party’s nomination to run for the White House again next year, with most polls placing him more than 30 points above his closest rival, Ron DeSantis.

As news of the indictment broke on Thursday night, many senior Republicans rallied around the former president.

House Speaker Kevin McCarthy said: “Today is indeed a dark day for the United States of America.”

He added: “I, and every American who believes in the rule of law, stand with President Trump against this grave injustice.”

DeSantis said that federal law enforcement had been “weaponised” in America and a “DeSantis administration will bring accountability to the DOJ, excise political bias and end weaponisation once and for all”.

And presenters on Rupert Murdoch’s Fox News, which until recently appeared to have cooled on Trump, said there was something nefarious about the timing of the indictment, which occurred hours after Fox News Digital ran an unsourced story alleging Biden had years ago been paid $5 million by an executive of a Ukraine national gas firm where his son, Hunter, was a board member.

Loading

The news that Trump is facing federal charges comes 17 months before the next election, and two months before the first Republican presidential primary debate. This week, the already crowded field of candidates seeking to run for president got even larger, with the entry of Trump’s former vice president, Mike Pence, former New Jersey governor Chris Christie and North Dakota Governor Doug Burgum.

But Trump is not the only person to come under investigation for their handling of classified documents. On November 2 last year, six days before the US midterm elections, Biden’s personal lawyers unexpectedly found classified documents, from his time in the Obama administration, at the Penn Biden Centre think-tank in Washington, DC, where he had an office after his vice-presidential term.

The records were handed back to the National Archives immediately, in contrast to Trump’s attempt to thwart the investigation into his own matter. Weeks later, Biden’s lawyers confirmed a “small number” of additional classified documents were found at two locations in the president’s home. The inquiry, by special counsel Robert Hur, is yet to conclude.

Classified documents were also found in Pence’s home, but the department last week said the matter had ended and no charges would be laid.

Get a note directly from our foreign correspondents on what’s making headlines around the world. Sign up for the weekly What in the World newsletter here.