Two political staff have been jailed for leaking a secret memo about talks between George Bush and Tony Blair.
Civil servant David Keogh, 50, from Northampton, was found guilty of two offences under the Official Secrets Act and jailed for six months.
The memo recorded Oval Office talks between Mr Bush and Mr Blair about Iraq in 2004, the court was told.
MP's researcher Leo O'Connor was jailed for three months after being found guilty of one Official Secrets offence.
The judge ordered Keogh to pay £5,000 of the £35,000 prosecution costs.
Few details of the "highly sensitive" memo have been made public.
The trial heard that Keogh, a communications officer at the Cabinet Office, gave the memo to 44-year-old political researcher O'Connor, also from Northampton, at a dining club in the town.
It was passed to Northampton South MP Anthony Clarke, who called the police.
The judge told Keogh: "You decided that you did not like what you saw.
"Without consulting anyone, you decided on your own that it was in the best interest of the UK that this letter should be disclosed.
"This disclosure was a gross breach of trust of your position as a Crown servant."
O'Connor, who worked for anti-war Labour MP Mr Clarke, said he had been approached by Keogh and told about "some quite embarrassing, outlandish statements" in the four-page document.
The meeting took place in April 2004
But he told the jury that he took the claims with a "pinch of salt" and never intended to send copies of the document to newspapers or MPs.
Rex Tedd QC, for Keogh, told the judge that Keogh had not acted for a political motive but had been following his conscience.
He said: "He acted out of conscience. No doubt, he did so misguidedly and he did so in a way which was likely to cause damage."
John Farmer, defending O'Connor, said the war in Iraq was "the most controversial foreign affairs involvement of this country since Suez 50 years ago".
Mr Farmer told the judge that the researcher has simply been unlucky to be in the position of working for anti-war MP Mr Clarke.
A spokesman for the Stop the War Coalition, who condemned the prison sentences, said: "While not a single government minister has been held to account for the disastrous policy of war in Iraq, two men are imprisoned for trying simply to shed some light on Tony Blair's relationship with George Bush."