Christmas trading will be safe from shortages caused by supply chain disruptions, shipping company Maersk chief executive Soren Skou has assured.
"At least that's what I'm hearing from our customers," he told the BBC.
There have been warnings that logjams at ports in the US and UK will lead to shortages at Christmas, and the port of Los Angeles has started operating 24 hours a day to clear the backlog of cargo ships.
Skou said that a shortage of workers in the ports to unload ships and a lack of truckers was behind the problems.
He told the BBC that Maersk, which handles almost 20% of the world's shipping containers, is chartering more ships, keeping ports open longer and has opened more warehouses to help.
Skou estimated that around 300 large container ships are waiting outside ports all over the world, including 80 in Los Angeles, a "few" outside Felixstowe in the UK and others outside Shanghai and Ningbo in China.
The port congestion is the result of huge consumer goods orders by people stuck at home because of the COVID-19 pandemic and their demand shows no sign of easing.
"The reality is that consumer demand is strong and at the same time our customers inventories are low," said Skou. "They both need to serve the consumer here and now, but also rebuild inventories and that's why we have an unprecedented demand situation."
Simon Heaney of the maritime research firm Drewry told the BBC that "port congestion is worsening while the number of ships waiting outside major ports around the world is increasing".
He said keeping ports open for longer is not a solution if there is a shortage of staff to run them.