A near-record fine imposed on UBS, the Swiss financial group, by Britain’s financial watchdog is part of an unfolding investigation into the past management of Indian private banking accounts, including two linked to the tycoon Anil Ambani, the Financial Times has learned.

The India-related activity – over which UBS was penalised £8m last week – has spawned an investigation by the country’s government into possible misuse of the bank’s accounts, while the UK’s Financial Services Authority is probing the conduct of former UBS employees.