Margaret Thatcher: Ronald Reagan's 'comrade in arms'
9 April 2013 Last updated at 00:07 BST
Ronald Reagan's chief of staff has recalled the close working relationship between the former US president and Margaret Thatcher, the UK's only female prime minister.
"They painted in primary colours, they didn't do pastels," said Ken Duberstein, speaking to the BBC's Katty Kay.
"It was a love affair in the right sense of the word," he added, saying President Reagan and Lady Thatcher were "partners", "comrades in arms" and "had each other's back".
Lady Thatcher, sometimes called the Iron Lady, died on Monday at the age of 87 following a stroke.