P&O Cruises is offering free cabin upgrades in March on a selection of 67 cruise holidays on all seven ships in the fleet, departing between June and December 2012, the company said in a statement. 

"The Ultimate Upgrade promotion is valid on bookings made throughout March, and entitles customers to a higher grade cabin at a lower grade price. All cruises in the promotion depart from Southampton and are between two and 35 nights in duration, to a choice of destinations such as the Mediterranean, Baltic, Canary Islands, Caribbean, USA and Canada, Norwegian Fjords, Iceland, and Around Britain," the company said. 

P&O Cruises managing director, Carol Marlow, said: “Customers booking in March will receive a fantastic value cruise holiday, offering the kind of cabin that may normally not be affordable for an even better cruise experience. This summer or autumn you could be enjoying a stunning view of the fjords from your  balcony or toasting the Caribbean sunset from a suite; all for less than expected, thus highlighting the unbeatable value for money offered by a cruise holiday."