A civil servant has been jailed for six months for breaching the Official Secrets Act after he leaked an "extremely sensitive" memo detailing talks between George Bush and Tony Blair.
David Keogh, a Cabinet Office communications officer, passed on the document to Leo O'Connor, a researcher for anti-war Labour MP Anthony Clarke.
O'Connor was found guilty of a similar charge and sentenced to three months in jail on Thursday.
The document's contents were considered so explosive that much of the Old Bailey trial was held behind closed doors.
Sentencing him on Thursday, trial Judge Mr Justice Aikens said Keogh's "reckless and irresponsible" actions could have cost British lives.
Keogh, who believed it exposed Mr Bush as a "madman", hoped it could be used to raise questions in the House of Commons and also wanted it to be passed on to US presidential candidate John Kerry.
O'Connor placed it in Mr Clarke's constituency papers but the Northampton South MP handed it in to Downing Street and an investigation was launched, leading to the Old Bailey trial.
During legal argument it emerged that Mr Blair wrote a letter personally thanking Mr Clarke for the return of the memo.
Keogh, O'Connor and Mr Clarke had all been members of a now-defunct political dining club in Northampton, where they all lived.
A jury on Wednesday found both Keogh, 50, and O'Connor, 44, guilty of making a damaging disclosure under the Official Secrets Act.
