Carnival has bought back almost $3bn in common stock over the past few years through a share repurchase programme designed to return money to shareholders.

The New York-listed cruiseship owner has repurchased more than 56 million shares valued at $2.7bn since resuming a share repurchase programme in October 2015 that began in 2013.

Carnival's board of directors has authorised three $1bn initiatives so far, with a fourth begun in April.