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.
More top news
One hundred years after the First World War began, British taxpayers are still servicing the loans taken out to finance the conflict.
FIFA have deleted a video they published showing Crimea as part of Russia in a promotional video for the 2018 World Cup
A cat who survived a brutal beating because he looks like Hitler has battled back from the brink of death to make a full recovery.