Former White House national security adviser John Bolton claims President Donald Trump told him to assist in a campaign to coerce Ukraine’s government into announcing investigations for Trump’s personal political gain, according to The New York Times.

The Times published the bombshell report, which it attributed to Bolton’s unpublished book, just before Friday’s resumption of Trump’s Senate impeachment trial on charges of abuse of power and obstruction of justice. It provides further reason for senators to hear from witnesses, particularly Bolton and the other White House officials he reportedly says were in the room.

However, it’s unlikely to change anything: Republicans already had enough votes to block witnesses, and are expected to do so later on Friday.

According to the Times report, Trump during an Oval Office meeting in May allegedly directed Bolton to call Ukrainian President Volodymyr Zelensky to make sure Zelensky met with Trump’s personal lawyer Rudy Giuliani to discuss investigations targeting Trump’s political rivals. Giuliani was the point person in Trump’s shadow foreign policy mission intent on forcing Ukraine to investigate 2020 Democratic candidate Joe Biden, witnesses said during House imnpeachment proceedings against Trump. Bolton writes that he ignored Trump’s order and did not call Zelensky.

The account of Trump involving Bolton in a quid pro quo arrangement with Ukraine adds further weight to the impeachment charges against the president. Bolton alleges that Trump directly orchestrated the pressure campaign, and had an obsession with Ukraine based on inaccurate information and conspiracy theories, the Times reported. Bolton also claims that White House acting chief of staff Mick Mulvaney, White House counsel Pat Cipollone and Giuliani were in the room when Trump ordered Bolton to call Zelensky.

Trump denied Bolton’s recounting of events in a statement and claimed the meeting Bolton described never took place. Giuliani called Bolton’s description “absolutely, categorically untrue.”

The meeting Bolton describes in his book draft reportedly took place months before Trump’s July phone call with Zelensky in which he requested investigations targeting Biden. It alleges that senior Trump administration figures were aware of Trump’s quid pro quo campaign long before the details of that call became public as a result of a whistleblower complaint.

Bolton has been a central figure looming outside of Trump’s impeachment trial, with Democrats demanding that he should be allowed to testify and Republicans seeking to block that from happening. The White House has also sought to prevent Bolton from publishing his book, and Trump’s lawyers in the impeachment trial have argued the manuscript is inadmissible.

Republicans on Friday appeared set to vote against allowing witnesses to testify in the trial, forestalling the possibility that Bolton would become its star.

Leah Millis / Reuters U.S. national security adviser John Bolton reportedly writes in a draft of his upcoming book that President Donald Trump was personally directing the campaign to pressure Ukraine into announcing an investigation for personal political reasons.