A sharp divide is emerging between the banks that will and will not pay guaranteed bonuses, giving rise to rancour from some groups at the “aggressive hiring” on trading desks by rivals. Those banks that have tried to be disciplined are becoming dismayed at the latest land grab for talent.

Bonuses obsess many who work in finance, and now more than ever they are a necessary way to bolster the basic pay they can offer staff. But can you buy loyalty?