A systems outage disrupted operations at many McDonald's stores in Japan and other countries on Friday, according to the U.S. hamburger chain and its Japanese unit.

The problem forced many of its restaurants in Japan to close or slow sales Friday, and some stores remain temporarily closed Saturday, McDonald's Co. (Japan) said.

The issue left customers unable to make cashless orders over the counter and mobile orders via its official app, the operator said.

The global outage was "not directly caused by a cybersecurity event; rather, it was caused by a third-party provider during a configuration change," McDonald's Corp. said Friday in the United States.

Many markets are back online, but "the rest are in the process of coming back online," the Chicago-based company said.

"What happened today has been an exception to the norm, and we are working with absolute urgency to resolve it...we sincerely apologize for any inconvenience this has caused," Brian Rice, global chief information officer of the firm, said in the statement.

The problem caused disruptions at McDonald's restaurants in Britain, Germany, France, Australia, New Zealand, Singapore as well as Hong Kong and Taiwan and others, according to local media reports.

==Kyodo

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