Kate Middleton Baby Bump, Due Date [PHOTOS] Pregnant Duchess Names, Christens 'Royal Princess' Cruise Ship, Last Appearance Before Maternity Leave

Catherine, Duchess of Cambridge, performed her final official royal duty today when she attended the naming ceremony of the new Royal Princess cruise ship. The 31-year-old mother-to-be christened the ship as well, performing the traditional breaking of a champagne bottle on the ship's hull. Prince William's wife was officially designated the godmother of this new ship and her baby bump was clearly outlined against her black and white print coat.

Today's ceremony culminated with the smashing of the 4-gallon bottle of Moet and Chandon Champagne onto the hull of the newly named Royal Princess cruise ship. Apparently, the bottle was too heavy for the pregnant Duchess to lift! Luckily all she had to do was cut a ribbon that launched the bottle, which was attached to a line of rope for guidance, against the ship. Cheers from the crowd followed the smashing of the bottle.

"I name this ship Royal Princess, may God bless her and all who sail in her," Middleton announced, thus ending her last solo appearance before she goes on maternity leave to prepare for the birth of her first child.

The ceremony also included a formal blessing and a prayer from the Bishop of Winchester and a performance by pop star Natasha Bedingfield. Though the highlight of the day was the Duchess' christening.

Today's christening and naming ceremony in Southampton included a brief tour of the ship that included a visit to the ship's bridge where Kate got to stand in for the captain in a photo opportunity.

Nearly three decades ago, Kate's late mother-in-law Princess Diana performed a similar christening ceremony in the same location. The Duchess' appearance today has highlighted the importance of the new 3,600-passenger Royal Princess, which is currently scheduled to begin cruising the Mediterranean this summer.