With the economy enjoying its longest post-war period of growth, exports surging and the property market booming, Japan appears finally to have left its painful years of economic gloom behind it.

But in one respect, the country's lost decade has left a lasting mark that is now troubling the government of Shinzo Abe, prime minister. Nearly 10 years since introducing its own version of the "Big Bang" reforms that deregulated London's markets, Japan is in danger of losing its place among the world's leading international financial centres.