Britain's Queen Elizabeth II planned to hit former Ugandan dictator Idi Amin on the head with a ceremonial pearl sword if he "gatecrashed" a Silver Jubilee church service, according to a new book.
The little-known anecdote was revealed by the last Viceroy of India, Lord Mountbatten, in his diary. It is among archive materials disclosed in "Monarchy and the End of Empire", which details the Queen's role in the Commonwealth.
According to the Daily Telegraph, the archives seen by Philip Murphy, director of the Institute of Commonwealth Studies and author of the book, describe government plans to minimise disruption if Amin made an uninvited appearance in Britain.
In 1977, when it was feared that Amin would attempt to travel to join the Commonwealth Heads of Government Meeting (CHOGM), documents show Britain "drew up elaborate contingency plans, involving the anti-terrorist squad and police marksmen, to detain Amin on his arrival in the UK and to eject him from the country".
Despite his failure to appear, the book claims the Queen remained concerned about the possibility he would try to attend the Jubilee Service of Thanksgiving at St Paul's Cathedral on June 7.
Lord Mountbatten said he asked the Queen why she "looked rather cross and worried".
He wrote: "She laughed and said, 'I was just thinking how awful it would be if Amin were to gatecrash the party and arrive after all.'"
"I asked her what she had proposed to do and she said she had decided she would use the City's Pearl Sword, which the Lord Mayor had placed in front of her, to hit him hard over the head with."
The Ugandan dictator was responsible for a series of rights abuses and the expulsion of the Indian and Pakistani minority population of the country. Many of them fled to seek refuge in the UK.