Cyberattacks have disrupted European supermarket chains, affecting refrigeration systems at hundreds of stores in France and forcing a major grocer to shut down websites serving customers in Europe and the United States.

French Finance Minister Roland Lescure told Parliament on Tuesday that about 700 of the country's 10,000 supermarkets were affected.

He said there was no risk to France's food supplies but acknowledged that the attack "touches the heart of our food security." "It was a wake-up call for everyone," he said.