The chair of the Iraq war inquiry is to be questioned by MPs next week on the latest delays to his report, it has been announced.
Foreign Affairs Select Committee chairman Sir Richard Ottaway last week wrote to Sir John Chilcot asking him to appear before MPs after it was confirmed that the inquiry, set up in 2009, would not report until after the general election.
Sir John today confirmed he would give evidence on the morning of 4 February, but an inquiry statement said he would not discuss "the substance of the Inquiry's work" or shed light "on the ultimate date of publication".
The chair added: "My colleagues and I have served as members of this Inquiry longer than any of us expected would be necessary. But the Inquiry has been given the task of examining all of the significant aspects of the UK's involvement in Iraq over a period of nine years.
"The issues the Inquiry is considering are complex and controversial. To ensure that the conclusions we reach are well-founded it is essential that our approach should be rigorous and comprehensive.
"We are conscious of our responsibility - to the public and to all those whose lives have been deeply affected by the events we are examining - to discharge our duty thoroughly, impartially and fairly."
The committee said the inquiry chairman would be quizzed "on the preparation of his report and on the obstacles which remain before he can submit it to the Prime Minister."
Earlier this afternoon civil service chief Sir Jeremy Heywood, who also served as principal private secretary to former prime minister Tony Blair, denied that he had contributed to the delays.
He told the Public Administration Committee that he was "very frustrated" by the delays, but that he had taken a "very, very open approach" to the release of classified documents, with few redactions.
After being pressed repeatedly on whether individuals who had received letters informing them of criticisms about them in the report were holding up the delay, he said this was not true, to his knowledge.
"I have got absolutely no evidence to think that anybody in receipt of a Maxwellisation letter is deliberately trying to hold this up,” he argued.