WASHINGTON/LONDON • Snarls in supply chains and transportation are leading to rising prices and shortages in key economies, with officials stepping in to address the problem and instil a sense of calm.

US President Joe Biden was set to host a meeting yesterday to speak on the progress in addressing supply chain problems weighing on the economy and threatening the holiday season, while he challenges business and union leaders to do more to ease shipping backlogs.

The Port of Los Angeles is going to 24/7 operations as a step towards helping to ease the shipping snarl there and at the Port of Long Beach, a senior administration official told reporters ahead of the meeting.

In addition, the three largest carriers of goods - Wal-Mart , FedEx and UPS - plan to move towards round-the-clock operations to help speed the shipment of goods across the country, the official said.

Samsung, Home Depot and Target are also increasing their work in off-peak hours to accelerate the movement of goods.

"By taking these steps, they're saying to the rest of the supply chain, you need to move too," the official said. "Let's step it up."

This comes after US Treasury Secretary Janet Yellen earlier on Tuesday urged Americans not to panic, noting that price increases are not likely to last. "I believe it's transitory," Dr Yellen said in an interview with CBS News. "But I don't mean to suggest that these pressures will disappear in the next month or two. This is an unprecedented shock to the global economy."

In Britain, people are advised to buy normally for Christmas and that there would be no shortage of gifts after shipping containers carrying toys and electrical goods were diverted from the country's biggest port because it was full.

Maersk, the world's largest container shipping company, has diverted some vessels from Felixstowe port in eastern England because a lack of truck drivers means there is nowhere left to stack containers at the port.

"I'm confident that people will be able to get their toys for Christmas," Conservative Party co-chairman Oliver Dowden told Sky.

The supply crisis is driven in part by the global Covid-19 pandemic.

There are several factors behind the shortages of key raw materials and finished goods now plaguing retailers. They include factory outages in countries that have imposed lockdowns due to Covid-19; unexpected demand spikes for some goods as behaviour changed during the pandemic; and labour crunch in some instances.

In Britain's case, its exit from the European Union also exacerbated some of the problems by constricting immigration.

Britain is short of about 100,000 truckers, leading to queues at petrol stations and worries about getting food into supermarkets, with a lack of butchers and warehouse workers also causing concern.

Adding to the supply chain problem is the ongoing chips shortage, which has now hit Apple Inc, the world's most valuable company.

It joined a growing list of household names from Toyota to Samsung forced to cut back on business because of a global shortage of semiconductors.

Apple is now likely to slash its projected iPhone 13 production targets for this year by as many as 10 million units, Bloomberg News reported on Tuesday.

For months, Apple remained the one company that could secure the chips needed to keep selling its latest range of products, due to its well-managed supply chain and the prestige of meeting its exacting standards. But the recent setback has dashed hopes that the supply-chain crisis was easing.

"If this is happening to the most powerful company," it could happen to anyone, said Mr Neil Campling, an analyst at Mirabaud Securities.

AGENCE FRANCE-PRESSE, BLOOMBERG, REUTERS