US Secretary of State Mike Pompeo late Thursday ripped into John Bolton for his explosive memoir about working for President Donald Trump, calling the former national security advisor a "traitor."

"John Bolton is spreading a number of lies, fully-spun half-truths and outright falsehoods," Pompeo said in a statement.

"It is both sad and dangerous that John Bolton's final public role is that of a traitor who damaged America by violating his sacred trust with its people."

"To our friends around the world: you know that President Trump's America is a force for good in the world."

Pompeo said he had not yet read the book, "The Room Where It Happened," which the Trump administration is trying to block from publication.

US President Donald Trump is accompanied by US Secretary of State Mike Pompeo (left) and then national security advisor John Bolton (right) at a July 2018 press conference at the NATO headquarters in Brussels
US President Donald Trump is accompanied by US Secretary of State Mike Pompeo (left) and then national security advisor John Bolton (right) at a July 2018 press conference at the NATO headquarters in Brussels AFP / Brendan Smialowski

But according to excerpts published by major newspapers, Bolton said that Pompeo -- one of the rare aides never to clash publicly with Trump -- disparaged him in private.

According to The New York Times, Bolton writes that he received a note from Pompeo during Trump's historic first meeting with North Korean leader Kim Jong Un in Singapore, saying of the president, "He is so full of shit."

Pompeo traveled four times to North Korea in 2018 to jumpstart diplomacy for Trump, who has hailed his own efforts as worthy of the Nobel Peace Prize.

But Bolton wrote that Pompeo, a month after the Singapore summit in June 2018, dismissed Trump's North Korea diplomacy, saying it had "zero probability of success," according to the Times report.

Bolton is well-known for his hawkish views on North Korea and left in September shortly after Trump, accompanied by Pompeo, again met Kim on the Demilitarized Zone in Korea.