The Federal Reserve Bank of New York contacted Bank of England Governor, Sir Mervyn King, in 2008 to make recommendations about Libor rates and increasing its accuracy, according to an e-mail dated 1 June 2008.
It was sent to Sir Mervyn and his deputy Paul Tucker by the then president of the Federal Reserve Timothy Geithner, who is now the US treasury secretary.
Mr Geithner called for six changes he believed would improve the integrity of Libor.
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