The world’s biggest fast food company McDonald’s is suffering a chip shortage in Japan due to the global supply chain crisis.

For the home of the Big Mac though it is not a lack of semiconductors that is causing the problem.

The firm has said it is experiencing delays of shipments of the potatoes used to make its famous French fries.

As a result it will only sell small portions of its French fries in Japan from Friday until 30 December.

“McDonald’s Japan will temporarily limit sales of Medium- and Large-sized French Fries as a proactive measure to ensure customers can continue to enjoy McDonald’s French Fries.

“Customers will still be able to order Small-sized French Fries at all of our restaurants. To date, there have been no breaks in supply,” the company told the BBC.

McDonald’s said it usually imports the potatoes it uses from a port near Vancouver in Canada.

However, ships have faced delays due to flood damage and the impact of the pandemic on the global supply chain.

It will now turn to alternative measures, including flying supplies to Japan, the company said in a statement.

This is not the first time McDonald’s in Japan has been forced to downsize its portions.

In 2014, a protracted industrial dispute between 20,000 dockworkers, terminal operators and shipping lines at 29 ports on the west coast of the US caused a shortage of French fries.

In response McDonald’s Japan took the emergency step of only selling small portions of French fries while it flew in 1,000 tonnes of potatoes.

Separately in August this year, McDonald’s said it was facing supply issues affecting the availability of shakes and bottled drinks at its 1,250 outlets in the UK.

The company said a nationwide shortage of lorry drivers was one reason behind the disruptions: “A number of issues are impacting retailers in the UK at the moment, one of which is the nationwide shortage of HGV drivers.”

The company added that a “historic” shortage of drivers had been exacerbated by changes to rules following the UK’s exit from the European Union.