The high street retailer saw sales slide 2.1 per cent to £4.86bn for the six months to September 28.
Pre-tax profit declined 17.1 per cent to £176.5m after weak first half clothing and home sales.
The retailer hailed the performance of its food business which grew sales but saw clothing and home sales fall on the back of buying and supply chain issues.
Steve Rowe, chief executive of M&S, said: “Our transformation plan is now running at a pace and scale not seen before at Marks & Spencer.
“For the first time we are beginning to see the potential from the far reaching changes we are making.
“In clothing and home we are making up for lost time. We are still in the early stages, but we are clear on the issues we need to fix and, after a challenging first half, we are seeing a positive response to this season’s contemporary styling and better value product.”