The Australian brewer Carlton United Breweries has taken the decision to lock out over 300 of its brewery workers as tensions surrounding a pay dispute escalate. The lockout, at the brewer's Abbotsford brewery, will begin tonight and last for 24 hours. The workers are members of the Liquor, Hospitality and Miscellaneous Workers Union, who have been locked in a pay dispute with CUB for several weeks. Union officials claim the lock out will threaten Melbourne's beer supply.