SYDNEY (AFP) -- Dock workers at Australia's three major ports went on a 24-hour walkout Saturday after talks stalled over a protracted wages and conditions dispute, crippling about one-quarter of the nation's freight.

The powerful Maritime Union of Australia called the strike at terminals in Sydney, Melbourne and Brisbane over after deadlocked contract negotiations with major freight firm Patrick hit a fresh impasse.

A second strike was to begin on Monday in Fremantle, on Australia's resources-rich west coast.

Patrick said the work stoppage followed a failure of talks before Fair Work Australia, the industrial umpire, hitting "15 ships, carrying a total of 17,797 containers" -- about one-quarter of the nation's container freight capacity.

"It's unfortunate that hundreds of Australian exporters and importers including small businesses waiting for deliveries will bear the brunt of the MUA's actions," said Patrick director Paul Garaty.

"We will continue to seek to negotiate through the Fair Work Australia process, which is the proper way to handle this dispute, not by strikes which disadvantage Australians."

Patrick and the MUA have been at loggerheads for almost eight months over
pay and conditions and strike action was approved by industrial authorities earlier this year in the event of talks breaking down.

Dock workers want a six percent pay rise, increased superannuation, annual
and long service leave and a safety supervisor for every shift, following four deaths on the wharves in five years.

"It's about our conditions of work, about having a safe workplace, and about having a career," said Kevin Bracken, Victoria state secretary of the MUA.

"In the bulk and general business, 60 percent of the workers are casually
employed with no annual leave, no holidays, no long-service leave, no guarantee that they are going to work there ever again," he told ABC radio.

The previous workplace contract expired in October and Bracken accused
Patrick of stalling, saying it "doesn't want to make an agreement, and is using it as a wage pause for our members."

But Garaty said the union's demands "will add a further Aus$120 million to the company's costs over a three-year period, in addition to other claims that seek to reintroduce rigid work practices that would hamper productivity."

"To agree to the union's excessive claims with no productivity offsets would only serve to undermine Patrick's ability to compete and deliver job security in the long term," Garaty said.

Talks were due to resume next week and Garaty said Patrick was committed to a "fair and sustainable outcome for both parties... based on productivity
improvements."

The MUA and Patrick have a long history of clashes, the most famous of which -- a seven-week waterfront strike in 1998 -- was among the biggest and best-known industrial stand-offs in Australian history.