The win means the end of a long-standing relationship between the brand and Saatchi & Saatchi, which created the strapline: "Australians wouldn't give a Castlemaine XXXX for anything else. The last advertisements for the lager brand ran in 1999.
It also cements Mother's position on the Interbrew roster, along with its other work for the Vodka Source, GB and Boru Black brands.
Interbrew is gearing up to relaunch Castlemaine as its standard lager brand. It is phasing out the Heineken Cold Filtered brand as it introduces a higher-alcohol-content brand in the UK next year.
Since 1993, Carlsberg-Tetley has brewed and marketed Castlemaine in the UK, and Interbrew is seeking to grow it beyond its current position as the number-six lager brand.
It is thought that Mother's relaunch campaign will continue the Aussie humour of Saatchis' original ads to reinvigorate consumer awareness of the brand.
Marketing and advertising activity will be backed by repackaging from the branding agency JKR.
Bartle Bogle Hegarty has also been confirmed on the Murphy's Irish Stout account. It already handles the Boddington's account. BBH will relaunch Murphy's with a £5 million spend. A campaign is due to break in November, just before the brand transfers to Interbrew from the Whitbread stable.
Lowe, which already handles Interbrew's flagship Stella Artois work, has extended its roster position by winning the Bass Ale account from Mustoe Merriman Levy.
Lowe will also work on Labatt Cold Filtered as well as continuing on the main Labatt brand.
Media planning and buying for all the accounts will be handled by Starcom Motive.