U.S. President Joe Biden's 2024 re-election campaign will not concentrate on the legal cases against Republican front-runner Donald Trump, who faces four sets of criminal charges, a top Biden campaign aide said on Sunday.

Trump on Thursday was booked at an Atlanta jail on more than a dozen felony charges as part of a criminal case arising from the former U.S. president's attempts to overturn his 2020 election defeat in the state of Georgia.

"We're not going to focus on Donald Trump's legal problems," Biden campaign co-chair Cedric Richmond told ABC's "This Week With George Stephanopoulos" program.

Trump, who spent about 20 minutes at the Fulton County jail where his mug shot was taken, repeated his assertion that the prosecution - along with the others he faces - is politically motivated.

"What has taken place here is a travesty of justice," he told reporters. "I did nothing wrong, and everybody knows it."

In most opinion polls, Trump holds a nearly 40-point lead against his rivals for the Republican nomination to challenge Biden, the Democrat who defeated him in 2020.

Biden has so far remained mum as Trump has been charged with 91 felony counts in four indictments this year related to paying hush money to a porn star, unlawfully keeping classified documents and attempting to overturn the 2020 election.

(Reporting By Arshad Mohammed in Saint Paul, Minn.; editing by Grant McCool)