Chief Financial Officer Eoin Tonge said inflation in the food market in the 12 weeks to December was 2.7%, rising to 3.5% in December. "In those 12 weeks, we were behind the market," he said.
In clothing & home, he said consumers were not seeing price rises at the moment, but pressure in costs for freight and raw materials was building.
"There is an expectation that there will be a similar level of inflation in clothing as well, but that will only start to come in the coming months," he said.
He said M&S had worked with its suppliers to improve its value proposition but it was "inevitable" that some of the inflation coming into the marketplace would be passed on.
(Reporting by Paul Sandle; editing by James Davey)