Large banks offering an array of financial services are finding it harder to access capital in the wake of tougher regulation, the former head of Barclays told CNBC on Wednesday.
"For many years—really, for 25 years—consolidation, growth and increasing complexity was the trend and universal banking had a capital advantage. And I think today, there is a capital disadvantage in some ways for the universal banking model," Bob Diamond told CNBC in Cape Town from the World Economic Forum.
Diamond's career in global banking spans 40 years and appeared to peak in 2011 when he was appointed chief executive of leading U.K. lender Barclays. However, he only lasted 18 months at the helm, resigning in July 2012 following the bank's interest rate-rigging scandal.
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Diamond reappeared on the London financial scene at the end of 2013, co-founding Atlas Mara, a financial services group focused on sub-Saharan Africa that listed on the London Stock Exchange.