Singer Rihanna's former bodyguard Geoffrey Keating has decided to sue her for allegedly defaming him via multiple emails sent last year.

The 26-year-old singer has been hit with a lawsuit by Keating, from Ireland, who said that she made "nauseatingly offensive" and false statements in an email sent to him and his wife last July, reports tmz.com.

Keating said the star used the same defamatory allegations via a telephone call to his sister also.

The bodyguard worked as a security head for Rihanna on her Diamonds tour between October 2012 and July 2013 and said the comments have tarnished his reputation and damaged the future of his business.

His lawyer Gerald Kean was granted permission Monday to serve the singer with legal papers at her home in New York City.

"We're taking this battle very seriously. We are satisfied that the Irish courts will see justice at the end of the day," said Kean.