Sir John Chilcot
Sir John Chilcot, a former civil servant, led the Iraq War Inquiry Reuters

Sir John Chilcot's long-awaited report into Britain's involvement in the 2003 Iraq War will finally be published on 6 July, just under a fortnight after the EU referendum. The £9m ($12.9m) investigation was first opened in 2009 and Chilcot's conclusions were expected to be published in 2012 after the inquiry held its last hearing in February 2011.

But the 2.6 million word report has been hit by a series of delays, prompting frustration and discontent from across the political divide. The summer date had been agreed by Chilcot, a former top civil servant, and the Prime Minister David Cameron. It follows a national security checking process.

"[The July date] will allow suitable time for the Inquiry to prepare the 2.6 million word report for publication, including final proof reading, formatting, printing and the steps required for electronic publication," Chilcot said in a letter to the prime minister.

Cameron replied: "It is indeed good news that the national security checking process has been completed within two weeks, and without the need for any redactions. My officials stand ready to assist yours on the arrangements for publication."

The report and supporting documents will be published on the inquiry's website, alongside a guide on how to read the report. The inquiry also said arrangements are being made so that families of those who died as a result of the conflict in Iraq can have early access to the report on the day of publication.