Grocery giant Asda is making a u-turn on its four-day working week after employees complained of “feeling exhausted” as a result.

Asda brought in new flexible working patterns for managers in January, which allowed staff to work a 44-hour week over four days, rather than five, across 20 of its stores.

However, staff have complained about “physically demanding” 11-hour shifts, which left them “exhausted” on their days off, according to The Telegraph.

Staff with children also reported “difficulties with childcare and school drop-offs and pick-ups”, while those working late were impacted by timings when travelling on public transport.

A spokesperson for Asda said: “We began trialling four different flexible working patterns for managers in 20 stores last year.

“In April we announced that two of those trials, a new retail structure and five shorter working days, would run until the end of the year following positive feedback from colleagues in these stores.

“We will continue to test different flexible working patterns to assess how these can benefit our colleagues and our business.”

Asda has reportedly scrapped the trial and is said to be testing other working patterns as a result.

The news comes the UK’s largest trade union, Unison, urged the Labour government to introduce the right to a four-day week “for all” after its members supported the concept.