US prosecutors have told Donald Trump's lawyers that he is the target of a probe into his handling of classified documents after leaving the presidency, in a sign he might be indicted, US media reported Wednesday night.

The notice came from the office of special counsel Jack Smith, The New York Times, CNN and other new outlets said, and gives the clearest sign yet that prosecutors are moving closer to charging the former president, who is seeking a return to the White House in 2024.

The Times, citing "two people familiar with the matter," said it was not clear when Trump's team had been told he was subject in the investigation. 

Special counsel Smith, named by Attorney General Merrick Garland, has been looking into a cache of classified documents that Trump had stored at his Mar-a-Lago residence after leaving the White House.

The FBI carted away some 11,000 papers after serving a search warrant on Mar-a-Lago in August, and Trump could face obstruction of justice charges after spending months resisting efforts to recover the trove.

Trump has repeatedly denied any wrongdoing.

"No one has told me I'm being indicted, and I shouldn't be because I've done NOTHING wrong," Trump posted on his Truth Social network Wednesday.

"I have assumed for years that I am a Target of the WEAPONIZED DOJ & FBI," Trump, who has already been indicted in a separate case, added. 

Investigators have been scrutinizing several suspected attempts to obstruct them from getting access to documents and footage from a security camera near the storeroom at Mar-a-Lago where documents were kept. 

Trump has openly acknowledged taking and storing the documents, undermining his lawyers' suggestion that he took the stash inadvertently in the confusion of a chaotic departure.

Meanwhile, investigators have obtained an audio recording of Trump in which he acknowledges he held onto a classified Pentagon document after he left the White House, according to US media.

And on Monday, US media also reported that Trump's lawyers John Rowley, James Trusty and Lindsey Halligan met with Justice Department attorneys -- they were seen by reporters arriving at the DoJ building in Washington, but did not make any comment. 

The Washington Post reported at the time that Trump's lawyers had come to make their case that their client should not face any charges.

- 'Dramatic... and divisive' -

The former president has already been charged with dozens of financial crimes as part of an alleged hush money scheme to silence a porn star claiming she had sex with him, and is due to go on trial next March, in the middle of primary election season.

Trump is facing a growing list of Republican primary opponents, including his own former vice president Mike Pence, who avoided taking an absolute position when asked about the probe during a CNN town hall interview Wednesday night. 

"Let me be clear that no one's above the law," Pence said.

"I would just hope there would be a way for them to move forward without the dramatic and drastic and divisive step of indicting a former president of the United States," he added. 

Fellow 2024 candidate former Arkansas governor Asa Hutchinson took a stronger tack, urging Trump to drop out of the presidential race. 

"Donald Trump is the target of an ongoing criminal investigation and he should step aside & put the good of the country above his candidacy," he tweeted Wednesday night.

In addition to the hush money and documents probes, Trump is also being investigated over his efforts to overturn his 2020 election loss in the southern state of Georgia and his involvement in the January 2021 storming of the US Capitol by his supporters.

Other politicians have been found to have been in possession of government documents at their private homes in recent months. 

In January, Garland named a separate special counsel to examine whether President Joe Biden violated any law after the discovery of some classified documents at his former office and in the garage of his home in Wilmington, Delaware.

And Pence was recently cleared of any wrongdoing over materials he uncovered at his home in Indiana.

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