The move would mark a shift for the world's largest boxship tonnage provider, which has concentrated on buying and subsequently leasing vessels.

But the company is likely to be tempted by the booming secondhand market, where values for smaller containerships have quadrupled this year.

"We have been asked by our customers and third parties for potentially considering selling some of our assets,¡± said Bing Chen, chief executive of Seaspan and New York-listed parent Atlas Corp.

He told a conference call that the company was "considering and evaluating" the proposals.

Mr Chen said he "would be open-minded to considering the request¡± from potential buyers, which he did not name.

He added that any sales would most likely involve smaller ships in the classic panamax and sub-panamax sizes.