Deutsche Bank has given strict reassurances to hundreds of workers at its London investment bank that their jobs are safe from a broader cull of 18,000 staff across its global businesses. For many, however, this might not be enough.

As Germany's biggest lender kicks off a huge restructuring that will end with a substantially downsized corporate and investment bank, even workers in business lines not affected are looking for opportunities elsewhere, according to headhunters and rival executives.