Secret notes, e-mails and records of discussions involving Alastair Campbell, Downing Street's director of communications, and Geoff Hoon, the Defence Secretary, about David Kelly will be demanded by the judge investigating how the scientist met his death.
Lord Hutton wants access to all Downing Street and Ministry of Defence material to help him to uncover the events leading to Dr Kelly's death. The judge is also expected to want to see records of his "interrogation" by the Ministry of Defence to see if it was fair or "bullying", and to gauge his state of mind.
Lord Hutton has already written to the Ministry of Defence and Downing Street asking them to produce everything "relevant to the inquiry". Sources close to the inquiry made clear last night that Lord Hutton would expect to see all notes of conversations between Mr Campbell and MoD officials, including Pam Teare, the director of news, who confirmed Dr Kelly's name to the media.
A spokesman for the inquiry said: "They have to send anything they think is relevant. Anything the BBC or MoD or Downing Street have that relates to Dr Kelly they are supposed to send. If they have transcripts they have to send them. The initial request has told them to send what is relevant and he can come back and ask for more if he wants."
Such top-level notes, routinely kept by government departments, would not normally be released, even if demanded by MPs, because they are too sensitive. Their release could be extremely damaging.
MPs believe the confidential Whitehall records of the events that led to the release of Dr Kelly's name to the media may prove crucial in the inquiry. Records of all phone conversations by ministers about Dr Kelly, which are routinely made by private offices, may reveal whether Mr Hoon authorised that the scientist's name be leaked.
The judge will expect Mr Campbell to produce notes of discussions he held with journalists or civil servants to establish if he played a role in the leak or advised the MoD.
Opposition MPs said giving Lord Hutton access to all information was essential to the investigation of Dr Kelly's apparent suicide.
"It is vital he be shown all notes relating to the inner workings of government over this affair," Norman Baker, Liberal Democrat MP for Lewes, said. "Otherwise he will never get a full picture. The Government must be completely open and co-operative and not withhold anything."