This week's New Statesman carries my article The Iraq deceit, which reveals that the Cabinet Office has finally admitted that it cannot substantiate Tony Blair's claim that Iraq could develop a nuclear weapon in "a year or two". I am publishing two letters from the Cabinet Office.

• The first, from the office of the Cabinet Secretary, helpfully confirms "that all records relating to the production of the Government's dossier on Iraqi WMD in September 2002 and the subsequent inquiries are retained by the Cabinet Office."

• the second, is a final response to my Freedom of Information Act request, which asked what was the basis for the "between one and two years" timescale and a claim in an earlier draft that it would take "at least two years" for Iraq to get the bomb. In both cases, the timescales cited related to a scenario where Iraq might obtain fissile material from abroad. As I set out here, the Cabinet Office had previously declared the request exempt on cost grounds.

So the Cabinet Office has all the records but cannot find anything to substantiate Blair's - and the dossier's - claim.

Yesterday, John Baron MP challenged Blair on the claim at Prime Minister's Questions. Blair did not answer the specific question about the timescale. Baron has followed this up with a letter to Blair.