British police have been forced to intervene after two singing sisters started receiving death threats over a string of ads the duo made for a UK bank.

Sisters Nicola and Rosie Dempsey go under their stage name of ‘Flo & Joan’ and started appearing in musical ads for the Nationwide Building Society back in December.

The string of ads have reportedly been quite divisive in the UK and now Nationwide has released a statement after death threats towards the pair began to escalate.

Some of the offending posts read: “Can any lawyers who follow me give me some legal advice on how much jail time I’d be looking at for a vocal chord assault on Flo and Joan off the Nationwide adverts? Many thanks.”

While another added: “So who’s chipping in to get these two singing sisters from the Nationwide advert brutally murdered?”

Another read: “I hope Joan and Flo are in a car accident with James Corden and Ed Sheerhan. All dead. Who wins? Society.”

Commenting on the threats, the sisters told Ok! magazine: “It’s one thing not to like an advert, another to threaten to kill the stars of it. Abuse is abuse and that’s never okay in our book.”

The building society is now working with London’s Met Police and other bodies to tackle the threats made against the duo.

Sara Bennison, Nationwide’s chief marketing officer, said: “Social media has provided a great instant barometer of reaction – good and bad. The huge amount of likes and shares have been great. But then there are others who have chosen to post the most vile, abusive and misogynistic comments about the duo.

“It is not just our Flo & Joan adverts that generate these comments, it is also our adverts that feature people of different colours, backgrounds and perceived sexuality, which attract the most criticism. That’s why it is important to call out those persistent offenders who put out vile comments on a regular basis and who should really know better,” Bennison said.