Greek banks are coming under substantial selling pressure for the third consectuive day as markets remain sceptical that a third bailout for the country will be reached by 18 August. Greek officials are confident that the €86bn rescue package will be agreed in time for the next European Central Bank (ECB) repayment which is due on 20 August. But shares in the country's biggest bank, the National Bank Of Greece, are in free fall and have more than halved in value since the reopening of the Athens Stock Exchange on Monday.