Excerpts of an upcoming book have revealed that top US military officer, chairman of the Joint Chiefs General Mark Milley informally planned different ways to stop former US president Donald Trump and his allies if they attempt a coup or take other dangerous or illegal measures after the November election, reports CNN.

According to the book by Pulitzer Prize-winning Washington Post reporters Carol Leonnig and Philip Rucker, which will release next week, Milley and the other Joint Chiefs had planned to step down, one-by-one, rather than carry out orders from Trump that they considered to be illegal or dangerous.

The book, ‘I Alone Can Fix It’, journals Trump’s final year as the US president, and offer a behind-the-scenes look of how Trump’s senior administration officials and inner circle handled his unhinged behaviour after 2020 election loss. The authors also interviewed Trump for more than two hours.

According to the report, it was the first time in modern US history the nation’s top military officer was preparing for a showdown with the commander in chief because he feared a coup attempt.

The authors explained how Milley spoke to friends, lawmakers and colleagues about the threat of a coup, and the Joint Chiefs chairman felt he had to be “on guard” for what might come.

According to CNN, Milley viewed Trump as “the classic authoritarian leader with nothing to lose.”

An official close to the general told CNN that Milley will not publicly address the issues raised in the book.

The authors interviewed more than 140 sources for the book, though most were given anonymity to speak candidly.

Milley came to limelight in June 2020, when he joined Trump during his controversial photo-op at St. John’s Church.

Milley had already earlier in the year resisted Trump’s desire to call out regular troops to confront Black Lives Matter protests in multiple cities.

That left him highly suspicious of Trump’s motivations, especially after the election, when Trump began replacing top officials, including at the Pentagon, with close loyalists even though he only had weeks left in office.

“Milley told his staff that he believed Trump was stoking unrest, possibly in hopes of an excuse to invoke the Insurrection Act and call out the military,” the book says.

In a statement, Trump repeated his unfounded claims about election fraud but denied threatening a coup.

He derided Milley as someone seeking favor with the “radical left.”

“If I was going to do a coup, one of the last people I would want to do it with is General Mark Milley,” Trump said.