A senior diplomat has been named as the official responsible for losing secret Ministry of Defence papers.
An investigation into how the documents ended up at a Kent bus stop found no evidence of espionage but blamed an individual blunder.
The official responsible has been widely reported as Angus Lapsley, who was on secondment to the MoD from the Foreign Office.
The papers included documents relating to the likely reaction of the Russians to the passage of Royal Navy destroyer HMS Defender through waters off the coast of Crimea and to the UK military presence in Afghanistan.
The Guardian reported that Mr Lapsley was being lined up to be appointed the UK’s ambassador to Nato at the time of the incident in June.
He was working as director general of strategy and international, responsible for defence policy on Nato and the Euro-Atlantic area.
But following the loss of the papers he was removed from “sensitive work” and had his security clearance suspended pending a full review.
A department spokesman said: “The MoD takes the protection of its information extremely seriously.
“The investigation has independently confirmed the circumstances of the loss and the manner in which it occurred.
“The investigation has confidence that all secret papers were recovered, there was no evidence of espionage and there has been no compromise of the documents by adversaries.
“The individual concerned has been removed from sensitive work and has already had their security clearance suspending pending a full review.”