Former vice presidents typically receive six months of Secret Service protection after they leave office.

Harris’ protection was extended to one year, until January 2026, by then-president Joe Biden before he left office last January, the official said.

Harris in September will embark on a 15-city book tour for her memoir, 107 Days, about her unsuccessful presidential run.

She was the Democratic nominee for 107 days after Biden withdrew from the race in the weeks following a disastrous debate against Trump.

Trump went on to defeat Harris in November.

The letter to Harris, dated Thursday, says the termination of additional security is effective September 1, the official said.

CNN was the first to report the contents of the letter.

Kirsten Allen, a senior adviser to Harris, said in response to the move: “The vice president is grateful to the United States Secret Service for their professionalism, dedication, and unwavering commitment to safety.”

US Senator Adam Schiff, a California Democrat and frequent Trump critic, called the action “another dangerous reminder that there’s no agenda more important to Donald Trump than retribution”.

Harris announced in July that she would not run for governor of California in 2026.

Trump has also ended federal security protection for others, including those who have criticised him, such as former national security adviser John Bolton.

In March, he ended protection for Biden’s children, Hunter Biden and Ashley Biden.