ASDA has lost the “respect and support” of its staff, trade unionists warned today as hundreds of workers marched through central Leeds in protest at “punitive” contract changes.

About 1,500 GMB union members employed by the supermarket giant marched past the company’s headquarters on Wednesday to oppose the imposition of “contract VI.”

The contract is deeply unpopular among Asda workers as it denies them right to paid breaks and no longer guarantees that some staff do not have to work at weekends.