Passionate love letters penned by the poet John Keats to his fiancée, Fanny Brawne , are set to be displayed in London before heading to auction in the United States, following their dramatic recovery after being stolen four decades ago . Eight letters signed by Keats to Fanny Brawne will be displayed at Sotheby’s New Bond Street in London from May 11-15 before they are sold at Sotheby’s New York in June, the auction house said. They are expected to fetch between $1.5 million and $2.5 million (£1.11 million to £1.85 million). These messages, part of a larger collection of approximately 37 letters written by Keats to Brawne between 1819 and 1820, resurfaced this year in New York. They had been missing for nearly 40 years after their theft, only to be recovered recently. The correspondence offers an intimate glimpse into their intense relationship.…