The recent rationing of french fries by McDonald's in Japan due to a disruption of potato imports is spurring competitors to seize a bigger share of the market, triggering what social media users have called "a potato war."

The operator of McDonald's restaurants in Japan has said it will only offer smaller portions of its french fries for about a month from Jan. 9 at all of its roughly 2,900 stores nationwide. It is the second time in two months that the company has restricted the sales of its fries.

Flooding near a Vancouver port and a worldwide logistics disruption triggered by the coronavirus pandemic delayed potato imports from North America, leading the company to suspend sales of medium and large portions of fries for a week in December.