British ballerina Dame Margot Fonteyn was heavily involved in a plot with Fidel Castro to overthrow Panama's government, previously secret files have revealed.
The renowned dancer was arrested by the Panamanian authorities in April 1959 after her husband launched a failed coup attempt using 125 Cuban revolutionaries.
Fonteyn confessed to Foreign Office minister John Profumo - who was later involved in a notorious sex scandal - that she met Castro and took part in a mission to assemble rebels and weapons at sea for an attempted invasion of Panama.
UK officials were unimpressed by her "highly reprehensible and irresponsible" behaviour and expressed hopes that she would "keep away from Panama for a very considerable time", files newly released by the National Archives in Kew, west London, show.
Fonteyn was 39 and an internationally celebrated prima ballerina when she was arrested and held for questioning in Panama City prison on April 20 1959, provoking huge publicity worldwide.
A few days earlier she and her husband, Dr Roberto Arias, the son of a former Panamanian president, had set out to sea in their yacht Nola, ostensibly on a fishing trip but in reality to gather men and arms for the coup. On April 19 the couple failed to turn up for a reception in Panama for the visiting Duke of Edinburgh hosted by the British ambassador, Sir Ian Henderson.
The following day Fonteyn returned in the yacht to the port of Balboa in Panama City, accompanied only by the captain and unable to explain where her husband was. She agreed to go to the home of the chief of the secret police, Hector Valdes, where she was detained and taken to prison.
Sir Ian described how he and his officials tried to get access to her but were foiled by local officials and politicians "as elusive as eels". Eventually the ambassador was allowed to see her at 9pm on April 21 and found she was "a little confused" but physically well.
He noted: "I rather fancy that she had been allotted the prison 'presidential suite', generally reserved for political prisoners of high standing, and the English-speaking second lieutenant, detailed to look after her, was careful to provide fresh flowers for her dressing table."
Early the next day Fonteyn was released and allowed to fly to New York, from where she returned to London.