Biden ducks questions on son Hunter's tax charges

US President Joe Biden kept silent Friday over new charges accusing his troubled son Hunter of avoiding tax while spending millions on an "extravagant lifestyle" including drugs and escorts.

Wearing sunglasses and a dark suit, the president waved to reporters but did not comment when asked if he believed his son was innocent, as he left the White House to board his Marine One helicopter for a trip to Nevada and California.

The Democrat leader, who is seeking reelection next year, will unveil major rail investments including the United States' first high-speed train, between Las Vegas and Los Angeles, before taking part in campaign receptions.

Hunter Biden was indicted on multiple counts on Thursday of evading at least $1.4 million in tax between 2016 and 2020, the second time he has been charged by a special counsel investigating his personal and business dealings.

"The defendant spent millions of dollars on an extravagant lifestyle at the same time he chose not to pay his taxes," special counsel David Weiss said in the indictment.

"The defendant spent this money on drugs, escorts and girlfriends, luxury hotels and rental properties, exotic cars, clothing, and other items of a personal nature, in short, everything but his taxes."

The previous charges accuse Hunter Biden of lying about his drug use on a federal application when he purchased a gun.

The new charges serve up more embarrassment for Joe Biden as he heads for a likely rematch with Donald Trump next year, and fends off a Republican bid to impeach him on grounds that he benefited from his son's overseas business dealings.

Hunter Biden, 53, is a Yale-trained lawyer and lobbyist-turned-artist, but his life has been marred by alcoholism and crack cocaine addiction.