White House concerned about the contents of the book
The New York Times reported over the weekend that a manuscript of the book details the allegations from ex national security advisor John Bolton that Pres. Trump held back payments to Ukraine until an investigation into Democratic candidate Joe Biden and his son Hunter.
Bolton has said that he would be willing to testify in the Senate impeachment trial if subpoenaed. Meanwhile Trump has suggested that he might attempt to assert executive privilege in block holdings testimony.