Qatar Investment Authority (QIA), the Gulf state’s sovereign wealth fund, is reportedly in talks with private equity groups and banks about approaching the high street chain. A bid for the retailer would mark the biggest private equity takeover of a British blue chip firm since Alliance Boots was snapped up by US buyout firm KKR for £11bn in 2007. However, M&S has been the subject of takeover speculation before and there are significant hurdles for any such deal to get the go ahead. Aside from the price tag needed to win over management and investors, M&S has a hefty pension deficit of around £300 million which means the scheme’s trustees have a significant say in any deal. Other bidders have tried and failed to bag M&S in the past, with Topshop tycoon Sir Philip Green launching an unsuccessful hostile £10bn bid in 2004. Private equity firm CVC, which owns Formula One, is said to have considered a bid for M&S last summer but pulled out after its plans were made public. QIA, which was not immediately available for comment, is no stranger to the UK retail sector. Its Qatar Holding subsidiary bought Harrods three years ago for £1.5bn and it has a 25 per cent stake in Sainsbury’s.