Central banks will need new tools to effectively implement negative policy rates if “secular stagnation” persists, Kenneth Rogoff told a seminar organised by Central Banking.

Rogoff told the audience it was impossible to say whether low real interest rates were going to prevail for the foreseeable future. But the future path of real interest rates, he argued, was going to have a crucial interest on central bank independence.

The professor of economics at Harvard University also called for