The meeting took place in April 2004
The leak of a secret memo from a summit between George Bush and Tony Blair came at an "extremely delicate" period in Iraq's occupation, a court has heard.
Martin Howard, then deputy chief of intelligence, was giving evidence at the Old Bailey trial of two Northampton men accused of leaking the document.
Civil servant David Keogh, 50, and MP's researcher Leo O'Connor, 44, deny three charges under the Official Secrets Act.
Mr Keogh is said to have passed a record of the meeting to Mr O'Connor.
The contents of the memo, considered so secretive that much of the trial is being held behind closed doors, have not been directly referred to in court by counsel or witnesses.
The leak was made just when the coalition was about to hand over authority to the Iraqis, said Mr Howard, second in charge of the coalition's defence intelligence staff at the time.
He was cross-examined about the timings of announcements about plans to arrest the anti-coalition cleric Moqtada al-Sadr, and operations in Fallujah.
Mr Howard said there was "great concern" that the transfer of power might be delayed because of insurgency in Fallujah and Najaf, and problems could extend to the British-controlled part of the country.
On Monday a statement by Mr O'Connor to police was read out in court, in which he said that the memo was a powerful document.
He said Mr Keogh wanted to get it into the public domain to influence elections about to take place in the United States.
Mr O'Connor told detectives Mr Keogh did not like President Bush.
The court heard that Mr O'Connor told police: "Something along the lines of 'The man's a madman' was said (by Mr Keogh).
"At the time it was the run-up to the American elections. I think his view was to get this document into this domain."
In another police interview read out in court on Tuesday, Mr O'Connor said he thought Mr Keogh wanted to use the document to embarrass the US rather than Britain.
"It was more of a Bush thing than a Blair thing. He talked about Washington and places like that.
"Bearing in mind the context, it wasn't just Iraq it was leading up to the presidential election."
The meeting in question took place at the Oval Office in April 2004.
The trial was adjourned until Wednesday.