Female workers will be disproportionately hit if a prediction of almost 1 million job losses from the UK’s retail sector becomes a reality, the industry’s trade union has warned.

Usdaw, the shop workers union, has written to the British Retail Consortium seeking urgent talks over a report from the trade group that suggested retailers could shed up to 900,000 jobs and close thousands of shops by 2025, as they adjust to rising labour costs and changing technology. The report said the jobs that survive would be more productive.

The dominance of women in the sector has raised concerns about them bearing the brunt of job losses. The BRC’s report said women made up 70% of lower-paid people in the retail workforce – those earning less than 20% above the minimum wage.

Usdaw’s general secretary, John Hannett, said the union was pleased to see the BRC “has recognised that low pay is an issue in the sector”. But he wanted more detail on what lay behind the 900,000 job loss prediction and its implications for workers.

“We are convinced that if the job losses come through in those numbers, there will be a bigger impact on women than men,” he added. “We are looking for urgent talks with the BRC to understand where they are coming from on this. What’s the rationale behind their predictions and how will they work with unions like ours to deliver high quality, better paid jobs?”

Women make up almost two-thirds (64%) of the membership of Usdaw, which is running a campaign for better support for parents and carers. Hannett said growing numbers were reporting being under pressure from the changing nature of the retail industry and struggling to balance caring responsibilities with employers’ demands in a “24/7 working environment”.