Federal prosecutors on Thursday rejected Donald Trump's attempt to have election conspiracy charges dismissed on the grounds that he enjoys immunity for actions he took while in the White House.

"No one in this country, not even the president, is above the law," special counsel Jack Smith's team wrote in a 54-page motion filed with the judge presiding over the landmark case.

Trump, the frontrunner for the 2024 Republican presidential nomination, is to go on trial in Washington in March of next year for allegedly conspiring to subvert the results of the November 2020 election won by Democrat Joe Biden.

The former president's lawyers, in a motion two weeks ago to US District Judge Tanya Chutkan, argued that the charges should be thrown out because Trump is "absolutely immune from criminal prosecution."

Prosecutors in the special counsel's office dismissed that argument and urged Chutkan to deny Trump's request.

"He is subject to the federal criminal laws like more than 330 million other Americans," they said. "No court has ever alluded to the existence of absolute criminal immunity for former presidents.

"The implications of the defendant's unbounded immunity theory are startling," they added.

"It would grant absolute immunity from criminal prosecution to a president who accepts a bribe in exchange for a lucrative government contract for a family member," they said, or "a president who sells nuclear secrets to a foreign adversary."

Trump's bid to invoke the presidential immunity defense is seen as a long shot by legal observers but it could result in a delay to the start of the trial as the argument potentially winds its way up to the conservative-dominated Supreme Court.

Trump's attempts to use the "absolute immunity" defense in other cases have been rebuffed by judges, but the nation's highest court has never ruled directly on whether a former chief executive is immune from criminal prosecution.

Trump is the first former US president to face criminal charges.