The 31st floor of 25 Bank Street – the old Lehman Brothers headquarters in Canary Wharf – is much like any other executive suite in the area: sleek, plush, anonymous.

But Kenichi Watanabe, the chief executive of Nomura who waits patiently for his guests in a regal armchair, is a man apart. Last week, he was in London for a round of meetings with investors, regulators and staff, before flying off to New York for a copycat round of meetings this week.

In the year since Mr Watanabe took the job, the 56-year-old from Kobe, 300 miles west of Tokyo, has conceived a bold mission: to transform Nomura from an Asia-focused investment bank into a global group with a strong base in London. Last autumn, he found a short-cut to realising that ambition by buying the European and Asian operations of the defunct Lehman only days after the Wall Street titan collapsed.