Gordon Brown said on Wednesday the world’s leading economies were close to agreeing a global bank tax, amid hopes in Downing Street that a deal can be concluded at the G20 summit in Canada in June. Mr Brown believes that opinion has shifted decisively in favour of a globally co-ordinated tax after President Barack Obama’s move last month to raise $90bn (£57.7bn) from a US bank levy. Gordon Brown The tax could cost the financial services sector tens of billions of pounds a year. The prime minister has strongly advocated some kind of charge on banks. “I’m interested in the...