Mr Cox said increases to the national living wage and National Insurance payments in the UK are also affecting firms which employ large numbers of people, including food manufacturers and those working in agriculture.
“We’re doing our best to offset those increases,” he said.
The society has to import fresh food daily, including bread, he said.
The Coop reported a “resilient” half-year performance at its special members’ meeting on both islands, with turnover reaching £119 million, up 4.6% year-on-year, with a net surplus of £685,000, up £1 million from the previous year.