The news comes as parent company Carnival attempts to rebuild its image following a number of incidents, including the Costa Concordia disaster off Italy.
However, Chris Hides, MD of M&C Saatchi PR, said the brief was unrelated to the accident, in which 30 people have been confirmed as having died.
M&C Saatchi PR have been brought in to help enhance the visibility of the Carnival brand in the UK through national, lifestyle, consumer, social and trade travel media.
Hides explained that although the company had a presence in the UK, it had brought in M&C Saatchi PR to build a profile in the market and ‘make much more noise’ around the brand.
He said: ‘Carnival Cruise Lines’ holiday philosophy is built around fun, which is a dream for us as a creative PR agency,’ before adding ‘this is about bringing that personality to life'.
Among upcoming activity for the company in the UK sector is the launch of Carnival Breeze in the Med this year, and a £100m refit of Carnival Sunshine, which will also operate seasonally in Europe during 2013.
Erin Johnson, head of marketing UK and Ireland at Carnival, said: ‘Carnival has big plans to develop the awareness and increase demand for its cruises in the UK and Ireland.
‘The team at M&C Saatchi PR has some terrific ideas and tremendous enthusiasm for our brand that stood out from the rest. It is the perfect agency to help take Carnival to the next level.’
Earlier this month, Carnival Corp chief operating officer Howard Frank said that Costa bookings were down 80 to 90 per cent compared with a year earlier in the four weeks after the sinking of the Costa Concordia.