The UK's financial watchdog will not be taking its inquiry into the banking giant's alleged Swiss tax evasion further.

The Financial Conduct Authority will not pursue action against HSBC over allegations that its Swiss private bank helped wealthy clients dodge tax.

The FCA ended its investigation into the bank “several months ago” and HSBC was informed of this at the time, according to several media reports. The conclusion of the review was never announced to the public.

Both HSBC and the FCA declined to comment but the regulator highlighted that it has no powers as far as tax is concerned; that role in the UK is taken by Her Majesty’s Revenue and Customs. HMRC was given a leaked file of the Swiss private bank's account holders in 2010.

When the media storm over the alleged tax scandal erupted in February last year, the Swiss private banking arm's chief executive, Franco Morra, told WealthBriefing that the bank had moved on from its business model before 2008, to which the specific allegations relate. The FCA said in February that it was working closely with HSBC and other agencies to “ensure that any questions this may raise in relation to any current practices and culture of HSBC are addressed”.

In November, Hervé Falciani, the "whistleblower" and former IT employee who took data from HSBC's private bank in the Alpine state, was sentenced to five years in jail by a Swiss court. However, whether or not he will be incarcerated remains to be seen as he is living in France.

In June, Geneva prosecutors called time on a probe on the Swiss private bank, with neither HSBC nor its staff suspected of current criminal acts. However, German authorities have now opened an investigation into whether the Swiss unit helped clients evade tax, SonntagsZeitung reported on Sunday.