(AFP) - A New York grand jury on Thursday indicted Donald Trump over hush money payments made to a porn star during his 2016 campaign, making him the first former US president to face criminal charges.

The historic indictment of the 76-year-old Republican -- who denies all wrongdoing in connection with the payments made ahead of the election that sent him to the White House -- is certain to upend the current presidential race in which Trump hopes to regain office.

And it will forever mark the legacy of the former leader, who survived two impeachments and kept prosecutors at bay over everything from the US Capitol riot to missing classified files -- only to land in court over a sex scandal involving Stormy Daniels, a 44-year-old adult movie actress.

Trump's lawyer Susan Necheles told AFP she expects he will be arraigned on Tuesday next week.

Manhattan District Attorney Alvin Bragg's office confirmed that it had contacted Trump's lawyers Thursday evening to "coordinate his surrender" in New York -- with the felony charges against him to be revealed at that point.

Trump slammed the indictment as "political persecution and election interference," raging against prosecutors and his Democratic opponents and vowing that it would backfire on his successor, President Joe Biden.

Surrendering for arraignment over what CNN has reported could be as many as 30 counts related to business fraud would normally involve being fingerprinted and photographed, potentially even handcuffed.

In the Republican camp, Trump's allies and sons denounced what they say is a vendetta aimed at derailing his 2024 campaign -- while his expected challenger for the party nomination, Florida Governor Ron DeSantis, slammed the indictment as "un-American."

Kevin McCarthy, the top Republican in the House of Representatives, said the indictment had "irreparably damaged" the country. Trump's former vice president and possible 2024 challenger Mike Pence called it an "outrage" that would only "further serve to divide" the United States.

But the top Democrat Adam Schiff -- lead prosecutor of Trump's first impeachment in 2019 -- called it "a sobering and unprecedented development."

"The indictment and arrest of a former president is unique throughout all of American history," Schiff said in a statement. "But so too is the unlawful conduct for which Trump has been charged."

Daniels welcomed the development with her characteristic aplomb.

"I have so many messages coming in that I can't respond...also don't want to spill my champagne," she tweeted while also plugging her #TeamStormy merchandise.

- Possible protests -

On March 18, Trump had declared he expected to be arrested within days over the payment to Daniels -- who received $130,000 weeks before the election that brought Trump to power, to stop her from going public about a tryst she claims they had a decade earlier.

In predicting his indictment, Trump also issued a call for demonstrations and dark warnings that it could lead to "potential death & destruction" that "could be catastrophic for our Country."

His statement set New York on edge for possible protests but the prospect of a quick indictment appeared to recede as the grand jury panel continued to hear witnesses -- until Thursday.

A media scrum quickly gathered outside the district attorney's office, along with a handful of anti-Trump protesters -- but the situation was calm overall.

Trump's ex-lawyer Michael Cohen, who has testified before the grand jury, told Congress in 2019 that he made the payment to Daniels on Trump's behalf and was later reimbursed.

Prosecutors argued the checks were not properly registered, and the jury was asked to consider if there had been a cover-up, intended to benefit Trump's campaign by burying the scandal.

The New York investigation is the first to reach a decision on charges out of three major probes into the former president.

Trump also faces felony investigations in Georgia relating to the 2020 election and in Washington over the January 6, 2021 attack on the Capitol by the ex-president's supporters, who hoped to keep him in office after his election loss to Joe Biden.

- Republican frontrunner -

Trump, who is seen to be the frontrunner to be the Republican nominee in the 2024 election, has branded all of the investigations political persecution.

The impact of an indictment on his election chances is unpredictable, with critics and adversaries alike voicing concerns about the legal merits of the hush money case.

Detractors worry that if Trump were cleared, it could make it easier to dismiss as a "witch hunt" any future indictment in arguably more serious affairs -- such as Trump's efforts to overturn Georgia's election results.

The Manhattan charges will also likely juice turnout among Trump's base, boosting his chances in the party primary.

Trump staged his first presidential campaign rally in Texas on Saturday, addressing several thousand supporters -- far fewer than the 15,000 he had expected -- in the city of Waco, Texas.

"The innocence of people makes no difference whatsoever to these radical left maniacs," he told the fired-up crowd.

© Agence France-Presse