European banks will have to raise nearly €200bn ($260bn) in new capital or cut their balance sheets by nearly 20 per cent, to achieve the tougher new Basel III banking reform rules that start taking effect in 2013, a new study has found. The study by the Boston Consulting Group looked at the efforts of 145 large banks worldwide to comply with that ratio and found they need to raise €354bn in capital on top of what they had at the end of 2010 or cut their risk-weighted assets by €5tn or 17 per cent. Banks in Europe had significantly further to go than those in the US and Asia, which each faced a collective shortfall of slightly less than €70bn.