President Donald Trump's former National Security Adviser John Bolton is being investigated for possibly disclosing classified information when he published his memoir in June.
The US Department of Justice launched a criminal case after failing to stop the publication of The Room Where It Happened book.
Mr Bolton denies all the accusations.
In the book, Mr Trump is depicted as a president ignorant of geopolitical facts.
Mr Bolton, who served as MrTrump's national security adviser in 2018-19, also alleges the president's decisions are driven by a desire for re-election
At the time of publication, President Trump made it clear that he wanted his former aide prosecuted, describing him as "grossly incompetent" and "a liar".
The case would focus on Mr Bolton's claim that his manuscript had passed through a pre-publication national security review, and claims by critics that it did not complete that review.
A grand jury convened by the Department of Justice has now formally issued subpoenas to the Simon & Schuster publishing company and the Javelin Agency, which represents Mr Bolton.
In a statement, Mr Bolton's lawyer Charles J. Cooper said: "Ambassador Bolton emphatically rejects any claim that he acted improperly, let alone criminally, in connection with the publication of his book, and he will cooperate fully, as he has throughout, with any official inquiry into his conduct."
What does the book say about President Trump?
Many of Mr Bolton's allegations are based on private conversations and are impossible to verify.
Among them are the following claims:
- President Trump sought help from Chinese President Xi Jinping to win the 2020 vote, stressing the "importance of farmers and increased Chinese purchases of soybeans and wheat in the electoral outcome"
- He also said China's construction of internment camps in the Xinjiang region was the "right thing to do"
- President Trump was willing to intervene in criminal investigations "to, in effect, give personal favours to dictators he liked". Mr Bolton said Mr Trump was willing to assist Turkish President Recep Tayyip Erdogan over a case involving a Turkish company
- The US leader said invading Venezuela would be "cool" and that the South American nation was "really part of the United States"
- Mr Trump was unaware the UK was a nuclear power and once asked a senior aide if Finland was part of Russia
Just days before the book's publication, President Trump said the book was "made up of lies and fake stories".
"Many of the ridiculous statements he attributes to me were never made, pure fiction. Just trying to get even for firing him like the sick puppy he is!" Mr Trump said in a tweet.