Workers at four Woolworths Ltd distribution centres have moved towards possible strike action against the Australian retailer.

The National Union of Workers said approximately 1,300 members at warehouses in Brisbane, Yennora, Minchinbury and Barnawartha are preparing to launch industrial action, potentially at the same time.

The union said 96% of members backed the proposed strike but no site has yet endorsed the action.

The NUW members want improved wages and conditions. The union said Woolworths is forecasting a 4-7% increase in profits but offering employees a pay increase of 0-3.5%. “The workers want a fairer share of the company’s profits,” the NUW insisted.

In some cases, union members are also calling for the right for casual workers to convert to permanent, site rates of pay for casual workers and casual-permanent ratios. The NUW accused Woolworths of “discouraging” casual employees from applying for contracts with the company.

Highlighting the plight of casual workers, the union said: “Six casual workers at Woolworths in Larapinta recently applied to employed directly through Woolworths. All six workers are now looking for work.”

Officials at Woolworths could not be reached for immediate comment.