Global broker Aon Corp said at the weekend that it would be relocating its corporate headquarters from Chicago to London in a move that would provide greater access to emerging markets and take "better advantage of the strategic proximity to Lloyd's and the London market". Initially only 20 staffers will move to London, where in 2014 the broker is moving to the iconic Leadenhall Building, nicknamed the Cheese-Grater. The first 10 floors of the building will be known as the Aon Centre. Aon said that the shift to London would provide several near- and long-term financial benefits, including greater financial flexibility and improved capital allocation. Aon becomes the first US S&P 500 company to shift its domicile to the UK. With the move, expected to close during Q2, Chicago will serve as Aon's headquarters for the Americas but will not result in job losses in the Chicago area or the US. The group currently employs 6,000 people in and around Chicago and plans to add 750 positions at the Aon Centre in downtown Chicago and another 1,000 jobs around the US this year. Aon CEO Greg Case said that "the continued investment in our international operations and emerging markets is important to the growth of our firm". Mr Case and around half of Aon's executive committee plan to move to London. Aon already employs 5,000 people in the UK and is the prominent sponsor of the Manchester United football club. Moody's Investors Service said that the move will not affect Aon's ratings but could pose a "public relations challenge" in Chicago, where the group has been a leader in the local business community for decades.