Ex-Trump aide John Bolton has deal for book that may publish before 2020 election, reports say

President Donald Trump's former national security adviser John Bolton has suggested he has a lot to say about the impeachment inquiry facing his old boss, and while it remains to be seen if he'll ever testify to Congress about what he knows, he may offer revelations in an upcoming book, according to media reports.

Bolton has a deal with publisher Simon & Schuster to write a book that may publish ahead of the 2020 election, The Associated Press and CNN reported, citing unnamed sources.

The same literary agency that represented former FBI Director James Comey and the anonymous author of "A Warning" helped Bolton land the $2 million deal, according to AP.

Bolton – a national security hawk who was often at odds with Trump and other White House officials who favored a less interventionist foreign policy – left the administration in September. Trump tweeted that he asked for Bolton's resignation and that he "disagreed strongly with many of his suggestions." Two days later, he tweeted that Bolton was actually "holding me back" when it came to handling the crisis in Venezuela.

Bolton: Ex-Trump adviser refuses to appear for Ukraine testimony in impeachment probe

Trump-Bolton breakup was inevitable: They clashed over Iran, North Korea and more

But Bolton disputed Trump's version of his departure, tweeting that he had offered Trump his resignation and the president had told him, "Let's talk about it tomorrow."

"I will have my say in due course," Bolton told The Washington Post after his departure, adding that his "sole concern is US national security."

Bolton's name has repeatedly come up in the House impeachment inquiry into allegations that Trump used military aid as leverage to get Ukraine to open investigations that would benefit him politically. Witnesses said Bolton was highly critical of the effort and that he said he wanted nothing to do with what he characterized as a "drug deal."

He declined a request to testify in the impeachment inquiry and his lawyer told congressional Democrats he would fight a subpoena. But his attorney, Charles Cooper, also teased that Bolton was "personally involved in many of the events, meetings, and conversations about which you have already received testimony" and suggested that he could speak about "many relevant meetings and conversations that have not yet been discussed in the testimonies thus far."

Democrats have said they will not issue a subpoena for Bolton because of the time it would take to resolve a court battle.

"Fox News Sunday" host Chris Wallace asked Rep. Sean Maloney, D-N.Y., why Democrats were not willing to endure a delay in order to obtain testimony from Bolton, "perhaps the best witness other than the president as to what was going on inside the Oval Office."

"We would love to have Mr. Bolton's evidence," answered Maloney, who sits on the House Intelligence Committee. But he said the question was if the committee already had "sufficient evidence from credible witnesses."

Maloney said if the House impeached the president, the case would move to the Senate, "where there will be a trial, where witnesses like Ambassador Bolton will have an opportunity again to provide the information they know."

Maloney said he thought Bolton's testimony would not be "favorable to the president." But it is unknown what he would say if he testified, or what he might write in his upcoming book.

His hawkish stances did not mesh with a president who wishes to see the U.S. shoulder less responsibility in world affairs, and his White House exit was less than amicable. But Bolton is a staunch Republican who might be reluctant to hand Democrats political ammunition.

"Frankly, I don’t think anybody knows, except John Bolton, exactly what role he wants to play in this drama," said Aaron David Miller, a senior fellow at the Carnegie Endowment for International Peace.

Contributing: Bart Jansen and Deirdre Shesgreen

This article originally appeared on USA TODAY: John Bolton signs book deal, may publish before election, reports say