Donald Trump
Donald TrumpReuters

US President Donald Trump ordered the assassination of Syrian President Bashar Al Assad after the Syrian regime launched a chemical weapons attack on its own people in April, 2017, according to a new book by Washington Post reporter Bob Woodward.

According to Woodward's account, Trump called Secretary of Defense James Mattis and ordered Mattis to kill Assad immediately after learning about the attack in which at least 80 people were killed.

“Let’s f–king kill him! Let’s go in. Let’s kill the f–king lot of them,” Trump told Mattis.

The Secretary of Defense told the President that he would do it, but when he hung up the phone he told his aide: “We’re not going to do any of that. We’re going to be much more measured.”

The defense establishment drew up a more conventional response, and on April 7, 2017, President Trump ordered the launching of 59 cruise missiles at Syria's Shayrat airbase.

Other excerpts from the book deal with the shock felt by members of the president's staff who dealt with international issues which resulted from Trump's ignorance of those issues.

In one of the cases described in the book, Trump questioned the importance of the American presence on the Korean peninsula, given the high costs involved.

Woodward, who famously exposed the Watergate scandal in the 1970s, will release his book , Fear: Trump in the White House, on September 11.