Andrea Casiraghi and Tatiana Santo Domingo

Andrea Casiraghi and Tatiana Santo Domingo

Monaco's Andrea Casiraghi will marry on August 31.

The late Princess Grace's oldest grandson is due to tie the knot with his fiancée Tatiana Santo Domingo at the end of the month, USA Today has confirmed.

A spokesperson for the Palace of Monaco said: "The wedding will take place on August 31."

The 29-year-old royal has been engaged to the South American heiress for a year, and have been together for eight. The couple welcomed their first child, a baby boy named Sacha, on March 31.

The high society wedding, rumoured to be taking place inside the Palace, is expected to be a star-studded private affair with guests including Tatiana's fashionista friends like heiress Margherita Missoni.

Andrea, the son of Princess Caroline and her late husband Stefano Casiraghi, met Tatiana - whose father is the second richest man in Columbia, according to Forbes magazine - as a student at France's Lycée Fontainebleau when they were introduced by his younger sister Charlotte.

It was revealed yesterday (07.08.13) that Charlotte has some good news of her own and is set to marry comedian Gad Elmaleh, with whom she is expecting her first child.