John Major’s fears over Cambridge’s Churchill archive

But the released papers show that the cabinet secretary at the time, Sir Robin Butler, had explained how, in part, lottery money was being used to avoid the risk of future litigation.

“The £12.5 million referred to represents not only the purchase price for the purely private material but also an element of buying out the risk of litigation in which counsel assessed our chances of success as, at best, 50/50,” he had written.

“We are advised that we should proceed with the transfer as planned… and that delay could result in the collapse of the whole arrangement.

“This could lead to a break up of the archive, which is what we have been trying very hard to prevent.”